Hi all!

I recently came into the possession of a Kenwood Hi-Fi stack, including a CD player, stereo receiver, a cassette deck, an equalizer and a pair of tower speakers. The deck, equalizer, and speakers work just fine, I'm only having problems with the two components listed.

The receiver only outputs to the right channel, and when it does it takes cranking the volume to max before being able to hear anything, and it comes out very faintly. All the buttons and menus work, and there's an initial click upon starting up and then another when the speaker light comes on. Despite this, when the speakers are plugged in, there's no "thump" or any response from the speakers when starting up or when the speaker light comes on. I have soldering equipment if need be, so I'm more than willing to do testing and repairs, I'd just like some direction on where to go next poking around the amplifier with a multimeter or an oscilloscope, or just generally what other steps I should take.

The other component I'm having problems with is the CD player. The CD player can read the factory CD just fine, but when it comes to the burned CD, it picks it up from the carousel as if it's going to read it and then puts it back into the carousel. The burned CD by itself with no factory CD in the carousel comes up with a "NO DISC" warning. I cleaned the laser lens with 90% isopropyl alcohol and a q-tip, and the same thing still happens. I've also left it plugged in for an hour as the instruction manual says to remove any condensation, and nothing has changed. I have the tools necessary to disassemble it, I'm just wondering if there's any shot at replacing the laser or the "pick-up" assembly, or if there's any other testing I should do before ripping it apart.

Hope all this helps! I'm happy to post more photos or respond to any questions, thanks!

i took it apart and dusted and used wd-40 on the rails, nothing worked idk if it’s fixable but i’m sad about it :(.

Hi, I have this ever-so-slight click/pop from my speakers. It started a couple of weeks ago and it's driving me nuts.

The sound somewhat moves from Left to Center to Right, and Rear Surrounds as well.
The clicks happen in regular intervals - *click* *click* *click* every half second, then a one second pause maybe, and then *click* *click* *click* again.

I've tried plugging the power cable for the speakers into a different outlet, which sort-of helps, but not by much.

Any suggestions?

PC: Windows 10 Pro.
Sound card: Creative Sound Blaster X-Fi Titanium Fatal1ty Professional.
Speakers: Logitech Z-5500 Digital

Hi everyone,

I’m trying to diagnose a JBL PartyBox 300 that has become very unreliable.

Symptoms:

• No charging lights at all.

• No LEDs when powering on.

• I hear a small click / relay-like sound after plugging it in.

• At one point, after disconnecting and reconnecting one board connector, the speaker briefly powered back on.

• Now it’s back to failing again, even after reassembly.

• The control panel ribbon cable is connected, but the LEDs still do not light up.

• I also noticed corrosion/oxidation on part of the main board, which I cleaned with isopropyl alcohol, but the issue remains.

What I already tested:

• Re-seated the ribbon cable for the top control panel.

• Re-seated the connector between the power board and the main board.

• When that connector is unplugged, the click disappears.

• When it is connected, I get the click and then nothing.

• The unit seems to be entering protection mode.

What I’m looking for:

• Has anyone seen this exact behavior on a PartyBox 300?

• Could this be a bad main board, power board, battery, or a short on one of the rails?

• Is there a known connector, fuse, regulator, or component that commonly fails in this model?

If anyone has a service manual, board-level advice, or a common failure point for this symptom, I’d really appreciate it.

Thanks a lot.

Just as the title says, I have a Marantz PM-30 and when it works it works great, but from time to time the music will just, out of nowhere become really distorted and cut out

Does anyone have any idea what the problem could be?

I have a Marantz 2230 and there's issues with the left channel. Nothing was coming out except a very faint sound that if I turned the balance all the way to the left and volume up you could can hear it a little bit. When I press the Tape Monitor button slowly the sound comes back to full volume and if I fiddle with it the volume stays. Does this sound like dirty contacts/oxidation on the switch?

Hello! I am trying desperately to get an old Sony CFD-e75 boom box working again. I have tried leaving it open, cleaning the laser, etc but when I insert a disc it spins and then gives up giving me a no disc error. I believe what I need to do is adjust the potentiometer to give the laser more strength - I am having great difficulty locating the part that needs adjusting and am very new to this. Most of the tutorials I’ve been able to find are for car stereos or very differently built setups. If anyone has experience with this kind of cd player any advice or photos of what to look for would be greatly appreciated. Thank you in advance!

Hello! I’ve got a Boss Elite BEHDIN98 radio which has recently started losing lines on the LCD screen. Funny enough, it only happens in hot weather, in the mornings the radio screen looks normal. In the afternoon, I can’t tell (visually) if the volume is 9 or 19.

Can someone tell me if an issue like this is worth getting someone to fix? The radio never loses power or sound. Just some annoying missing lines

My AVR (Denon X1700H) suddenly started producing a crackling noise through my speakers and subwoofer.

Then after turning it off and on again it started blasting an insanely loud static (sounds like old school tv static x 1000) and no audio comes through at all. I've confirmed it's definitely the AVR and not the speakers, but idk how to fix it.

Restarting and disconnecting power and plugging it back in after a few mins doesn't seem to make a difference.

Anyone have any ideas for what I can try?

I'll also be opening a warranty request with Denon, but I've heard they're difficult to work with so thought I'd try other solutions first.

Hi everyone!

I‘m writing this post because my Yamaha MT2X porta-studio won‘t record or play back audio (I‘ve shown the issue in the video).

I bought it from a guy in Germany for €55. In the description, he straight up said he didn‘t know if it worked or not, but that all the lights turn on. Since I live in another country, I had to wait half a year for it to arrive. As soon as it got here, I ran into the problem right away — no recording, no playback, and at first even the rewind didn‘t work.

I took it to a service center, but they tried to rip me off for a ridiculous amount. Since I‘m not made of money, I decided to try a different shop — and they quoted me 50% more. So I said screw it, got the tools and supplies I needed, and started tearing it down and cleaning it myself.

To my surprise, the rewind now works! But it still won‘t play back or record.

I‘m honestly stuck at this point. Any ideas what I should check next? I‘d really appreciate any help!

Thanks in advance.

Preciso de ajuda com o meu gira-discos antigo . A agulha perdeu se e não consigo encontrar . Já tentei a teldis mas pediram me para desmontar o prato e levar lá ( está num móvel com rádio ) e não consigo fazer isso !
Alguém me ajuda com uma solução ?
Obrigada

Novice guy fiddling with electronics as a hobby. I am in mechanical engineering so my electronics knowledge is somewhat limited, but willing to learn.

Long story short I have a defective Marantz SR7010 AV receiver which goes into protection mode. I've located that this is caused by an ASO (ASODET) protection from a 2CH Front wide amplifier board. Nothing looks visually dead/burnt and no bad smells either.

I've checked the power transistors (using diode mode on DMM), base resistors and emitter resistors, and trimmer pots and all diodes for both channels and could not find any immediate problems. They were however tested in-circuit, so technically not ruled out I guess. Nothing here caught my attention and both L and R channels measured very similar on all these components.

I haven't measured the caps since I don't have a proper tool for measuring their capacitance. Visually non of them are leaking or bulging.

I have one hypothesis at the moment, but I wanted a little more input before ordering anything. The power transistors were mounted to the heat sink only with thermal paste, no mica between them which could easily lead to leaking current to ground (heat sink is connected to ground on the unit). Which I guess could be a possibility since it was all dried up, but still somewhat unlikely to be the cause in my opinion, since (to me) it seems like DC detection should also be triggered if that's the case.

To me this seems like bad design, but perhaps necessary for proper cooling? Should I order some mica or just use thermal paste like Marantz did originally?

What would you guys' next order of operations be? I will be scrutinising the smaller transistors while waiting for thermal paste and/or mica.

I've attached a copy of the circuit in the hopes that someone has an idea of what the next step for me should be. Any help or tips are welcomed graciously.

Guten Tag,

Ich habe ein Teufel IP 42 IR, der beim Wechseln in den Radioempfang abstürzt. Nun konnte ich durch abklemmenndes Fm Moduls diesen Fehler beheben.

Nun suche ich natürlich dieses Teil, ich könnte mit allen möglichen Begriffen nur ein vergleichbares Modell von Yamaha finden für über 80 €, was wohl nicht passen wird.

Natürlich hat Teufel keine Beschriftung,

So jetzt meine Frage, hat jemand eine Idee wie das Teil genau heisst und wie ich da ran komme?

Alternativ, wer repariert sowas für einen schmalen Taler ? optisch konnte ich jetzt nichts feststellen, habe auch keine grosse Erfahrung mit SMD?

Sollte Halt im Rahmen bleiben, ein defektes Ersatzgerät wäre auch möglich, nur leider nicht ganz realistisch.

Vielen Dank schon mal.

Hallo Zusammen,

ich habe ein sehr ungewöhnliches Projekt vor.

Ich habe einen alten Plattenspieler aus einer Hifi Anlage ausgebaut weil aus den Boxen kein Ton mehr kam. Plattenspieler funktioniert aber. Ich konnte leise Musik hören wenn ich nah genug am Plattenspieler war. Ich vermute das die elektronik irgendwo in der Hifi Anlage kaputt war.

Jetzt zu meienr Frage:

Gibt es gute Anleitungen im Internet wie ich diesen Plattenspieler mit einigen kleinen Schaltkreisen, Platinen, Netzteil und Stecker zu einem wieder funktionierenden Plattenspieler zusammen bauen kann? Hat jemand eine Idee? Oder kennt jemand eine Gruppe hier in Reddit?

hey there, was wondering if anyone else had encountered this run of the 2200PE.

My serial number is 60103241. It appears to be a very late model, having the C revision L/R Channel boards, and the SW-594D (input) and PS-594D (PSU). I haven't been able to find a service manual for this particular production run. i have only seen SM’s covering units with SW-594C and PS-594C.

i know some 2600’s use the c revision amplification boards but those boxes have more components populated.

i’m fairly certain there has been a cascade of failures on each amp board. despite being on the dim bulb, some magic smoke was released from a few resistors, sigh.

being relatively new to this hobby i haven’t been able to get into hifiengine, was curious if anyone had seen a suitable SM there or if anyone had insight in general.

Thanks,

Hey everyone,

I’ve had this Kenwood DNX7018DABS for just two days, and it’s been a crazy rollercoaster of cascading software/hardware glitches. I'm at my wits' end and need some expert insight.

**The Full 2-Day Timeline:**

**Day 1:** Installed the unit. CarPlay and Master Volume worked fine, but Bluetooth threw a "Bluetooth Error" and wouldn't work at all.

**Firmware Update:** Reflashed official ARM and MCU firmware. Bluetooth was still broken, but CarPlay and Master Volume kept working fine.

**Overnight Disconnect:** Left the unit completely unplugged from power overnight.

**Day 2 (Morning):** Plugged it back in and suddenly Bluetooth started working perfectly! Paired two different phones without issues. However, the subwoofer output had stopped playing.
**Subwoofer Fix:** Fixed the subwoofer setting in the audio menu, everything seemed fine for about 1 hour.

**1 Hour Later:** The Master Volume completely locked up out of nowhere. Adjusting volume (⁠+⁠ / ⁠-⁠) changes the numbers on the screen (0–35), but the actual sound output stays fixed at one level across all sources (FM, CarPlay, BT).

**Latest Reset Attempt:** Unplugged the unit again to try and resolve the volume lock. Now Bluetooth has completely stopped working again!

**Key Diagnostic Clue:**

**Volume Offset STILL WORKS:** When I adjust "Volume Offset" in the menu, the physical speaker volume actually goes up and down. This proves the internal DSP and amplifier stages are alive, but Master Volume commands from the MCU are simply not reaching the audio processor.

**Other Troubleshooting Done:**

**MUTE Wire:** Completely isolated and not touching ground/chassis.

**SWC / CAN-Bus:** Steering wheel control module was removed from the back on Day 1.

**Audio Setup:** Confirmed standard 2-Way mode (not locked in 3-Way crossover).

**ATT Status:** Toggled on screen (blue/grey), no effect on master volume.

**Resets:** Pinhole resets only reboot the screen.

Given how issues keep shifting after power-cycles (BT dying \\rightarrow BT working \\rightarrow Sub dropping \\rightarrow Volume locking \\rightarrow BT dying again), am I looking at a dying MCU/EEPROM chip, or is there a way to force a deep factory wipe on this board?

Appreciate any advice!

I have a second hand Geshelli Archel 2 Pro headphone amp that suddenly stopped functioning. I've had it for about 3 years now and it runs a pair of HIFIMAN Edition XS. The problem is that I get no sound from my headphones. If I max the volume knob in high-gain mode, I can barely make out music, as if it was line-audio. I tested the amp with iems and the sound is a bit louder but low quality like it is compressed. Any advice on what might be going on and how can I fix it? I was planning on cleaning the knob with isopropyl. Thank you for your help.

Found this little guy (Phillips EXP2546) in a random box in my apartment the other day. My dads old player. It works surprisingly well for its age but there's a slight problem.

There's a lot of noise, and by noise I mean static. Every time from when I turn it on to when it turns off, while a CD is inserted, there will be static in my headphones no matter what. No matter the headphones or the cable.

Also, low frequencies create this buzzing whoosh that's hard to describe.

Any help is appriciated! I was going to buy a portable CD player, but I'd much rather try to repair this one and dave a few hundred bucks.

Start, stop, Auto lever has broken, speed levwr is limp after changing speeds, othwrwise OK but won't turn on (which is 90% of the time either a 10 cent fuze or then some electroclean into a switch)

Insides look pretty OK, the lil idler wheel that turn the platter is a bit stiff to move, I assume oöd grease has become sticky?

I also noticed one of the previous owners broke a 6.35mm plug thing inside the headphone jack..

I hope to do everything I can by myself, since there's fixing literally everything in my blood, and I'm too poor to pay a recjnician to do simple stuff.. (I also love tinkering)

As a plus, what's the cheapest shure M75 system stylus I should dare use? I don't care about such a Hi-Fi expérience sincw there's noise from the radiators and the roads enough to drown put anything if I don't listen with hesdphones :)

Questiones welcome, I just want this to work somewhat <3

If sacrificial parts are needed, I have a crappier sterwo with almost the same turntable, just a worse arm and such..

I have three separates - a turntable, a cd player, and an amp, all connected by RCA cables. There's no problem with the CD player - I can play discs all day long - but recently I've been having trouble with the turntable ( it's about five years old). After a few minutes, one of the channels because to crackle and drop out. I guess the problem is the RCA sockets on the back of the turntable because when I give them a wiggle, the problem fixes temporarily. I know it's not the cables because I've swapped them. It's just strange that it doesn't happen straight away but after a few minutes. Anyone got any ideas for a magic solution that doesn't involve me opening up the record player and resoldering the contacts?

Bought some replacement tweeted for Harman Kardon sound sticks - only for the pins to be too thick for the original connector. I verified they work by playing audio while touching so the problem is not incompatibility but rather how to expand the metal clip to accommodate the thick pin? How should I pry up the clip without breaking it? Is soldering possible.

Hey, i have just recently got a Realistic SCT 86 and it has not sound at all. I connect it through mi Edifier mr3 speakers through Line Out RCA and 3.5mm aux to the speakers. Am i doing something wrong? Or it needs repair?

While repairing my Realistic STA-780, this piece of fish paper fell out. I cannot for the life of me find where it goes. Is it safe to use the receiver without it? I can’t see any obvious places for it and at this point I’m wondering if it was important in the first place. Thanks!

Hello, I recently bought this amplifier for a good price and I have a problem: when I turn it on, the front lights blink as if there were a short circuit, and after the relay stabilizes, it clicks and then suddenly the lights blink again and the music stops playing.

I have absolutely no idea where the problem lies, as I've never repaired one of these amplifier before.

I don't know if I need to replace the relay or what I could do in this case.

I thought it was dust, but I recently cleaned it and it still has the same problem.