In my 2018 legacy and on my new Samsung A535G phone sounds horrible to the recipients of my calls when using Bluetooth... my voice is garbled and I sound like a robot. The solution to this is to move the phone away from the radio... there seems to be some kind of lack of shielding in the Samsung phone that's causing the distortion. When I have my phone on it's magnetic vent clip by the radio this occurs when I move the phone away from the radio it's fine.
I get to troubleshoot a lot of
odd edge-case stuff for a living, so bear with me here.
Could it be the clip itself causing this? By moving it away you are actually testing two variables: 1. Distance 2. Disconnecting from the mount/clip
Keeping it attached to the clip and moving it away will isolate the distance variable. Bonus points for rotating the phone & clip at distance and see if the issue happens at some particular orientation of phone-clip-headunit.
Try holding the phone in the same rough position it would normally be in without the clip.
Wireless is great until you have an issue and then it's all funtimes to track it down.
Bonus story time: Once I had a client complaining that they couldn't get onto WiFi at their desk; which about 15' away from the router. I looked at the machine and it had no errors. Moving it near the router let it connect. I took it to another office and it was fine. Puzzled, I went back into their office and dropped it on the desk for a think.
Then I noticed that it was still connected. I had put it on the other leg of the L-shaped desk, and not the normal spot. I then moved it to the normal spot and WiFi dropped. I kept poking about until I figured out that the metal doorframe for the office's door was between the router and that exact spot the laptop usually lived in. The metal was absorbing the signal and casting a "shadow" over about 3' of the desk. The laptop got moved to the other part of the desk and all was well.