Hello. I bought brand new BV8000pro. I have problem with sound.
When listening to music, or something else, sound is great, but for 1second or less, after that sound volume drops about half ( volume bar is full)
this stuff happens with phone sounds ( allerts, tones etc) too. start melody is loud and perfect. hard reset does nor help

If a firmware update followed by a factory reset doesn't solve the problem, it looks like an hardware fault.
Please contact your seller to get a replacement under warranty.