Device: RFinder K1
Android version: 6.0
TS version: 3.2.3

No rx audio whatsoever upon connection or while connected. When the 'audio settings' screen is opened, the test audio sounds, including session notification sounds and talk-back echo voice test audio, all begin working. But once the 'audio settings' screen is closed, all TS audio immediately stops cold. All other audio/voice apps on the device work properly. An uninstall and reinstall of TS makes no difference. Clearing app cache and data makes no difference.

Others who own the K1 device but use previous TS versions do not experience this issue. I've been unable to find a safe source to download a previous TS version for Android (for testing purposes). Is such a source available? I'd like to start by trying v3.19 onward (if possible). Can someone point me to an apk link?

(Note: The Android release on my device (v6.0) cannot be upgraded since it is tied to special existing software and functionality.)