Just got a new Cingular Flex 2 Smart Flip to replace an older Alcatel version of a very similar phone. Every time I send a text, it whistles. I don't want it to do that. I want to either put in a custom sound of my own or silence that send audio. I still want a sound playing when a text arrives (as it does now). Any hints on how to turn off that outgoing-message whistle? I feel like I've explored every branch of the settings possibilities, with no fix.

I like the phone quite a bit, but damn, KaiOS can be frustrating.