Sim1I confirm this thing too.
Hello, today I updated my zen8 to the latest update, after that I can no longer lower the volume while listening to audio messages from front facing speaker (the one for calls). I tried rebooting without luck, cleaning whatsapp and telegram cache without luck. Is it now unusable, it seems to be stuck on max volume and the audio is distorted /painful. Before the update it was working perfectly fine.
In calls it seems to be working fine
Also another zen8 user confirmed that he aslo have this issue on telegram
I can't lower the volume on front facing speaker listening to audio messages from telegram/whatsapp