Anyone else experiencing the speaker during playback starting out at full volume then quiet down and sometimes mute during media playback?

I have the same problem...
Some the sound disappeare

You can have a try: Go to the dial interface and dial "*#87#".
Or you can contact our professional after-sales directly.
After-sales email: support02@blackview.hk

Did the loud speaker test, after 2 seconds it drops to half volume then, a second later goes away.

Same Problem here! *#87# is only for Testing.

I have the same problem.
It never happens with earphones.
When i restart the app there is a moment when the problem stops.

I'm having the same problem. I would like to know what the solution is to solve this uncomfortable problem.

Hello to all.

I have the same Problems with the speaker.
Exact as  [color=inherit]SnuffThePunkz[/color]     explained.   Is there a solution?

Facing same issue, please give us solution asap.

Yes, I have this same issue, glad to hear more people are having trouble with this. I have found multiple posts indicating Android 9 itself might be the culprit. 
Did some testing and tried reporting it (submit button not working) so sent it through mail to support02@blackview.hk

Below a summary of my form:

[color=#222222][size=100]Software Version:
BV9800_EEA_S65_V1.0_20191016v10_20191203-1020[/size][/color]
Your Feedback:
[color=#222222][size=100]Love this phone, but is has a very annoying issue which has impact on calls and primary function!

Two major symptoms:
- Using speaker, sound randomly dies after random period of use. Doesn't matter which app, no sound from speaker will work.

- Speaker is working for 1 second, sound "normalizes", then sound dies.
Switching apps, go back to video, sound plays very loud, gets normalized and dies in 1 second

I have tried the following:
- During call: enabled and disabled speaker
- Waiting
- Switching apps continously back and forth (1 second sound)
- Change all volume levels
- Enable and disable "Do not disturb"
- Enable and disable "Bluetooth"
- Enable and disable "Wireless"
- Enable and disable "Data"
- Enable and disable "Screen rotation"
- Left background apps open
- Killed all background apps
- Reinstalling apps
- Checked for updates, not available
- Rebooting phone

Results of testing:
-  No solution found.
Sometimes sound gets back and stays very loud.
Sometimes sound keeps gone.
Sometimes sound works with stuttering intervals of a few seconds/minutes
- Using headphones for music or calls, no issues found
- When headphones unplugged and no sound, it doesn't show headphone plugged in
- Using earspeaker (top speaker) for calls, no issue found when (bottom) loudspeaker fails
- Also affects calls!
Place phone call, enable speaker.
Other end will hear me fine, but speaker doesn't make a sound. When  switching to normal callspeaker no problem and I can hear other side. Back on (bottom) loudspeaker gives problems.

How to recreate:
- Play any sound content through speaker.
- Happens most often using Google Chrome or YouTube video (possibly due to being most used and thus noticed). When bug is live, no "music" sound can be produced.

- Will also happen randomly while using applications/games.

Seems like software issue, when switching application/forcing sound to restart it will often sound 1 second before killing sound.[/size][/color]

== end of form summary ==