Finally after half year I fixed it. The filesystem had error. I did:

• downloaded ubuntu iso on host machine
• attached iso as CD-ROM
• turned off UEFI
• turned off boot from hard drive
• set up CD-ROM as first device to boot
• started virtual machine and selected boot from CD-ROM
• after ubuntu started I launched gparted, selected disk with HA and run check/fix on data partition (twice)
• powered off virtual device
• unchecked boot from CD-ROM, checked boot from HD and moved it to first position
• moved HD in boot order to top
• started the virtual machine. no Ctrl-D was required

Source: UPDATE – System OS to 6.0 – Home Assistant OS – Home Assistant Community

1. Download MX player(for video) and playmusic/Spotify or any app for music/MP3 playback.
2. Open MX player
3. Then go to local Player settings> Player> Playback section> and uncheck play alone option.
4. Go to equaiizer settings (of max player) and make everything( all frequencies) to 0.
5. Now you can play any video on MX player with zero volume while simultaneously playing music using another MP3 player app at full volume.

Note! If you have a samsung device you can do it by samsung’s built in soundassistant settings.

https://www.quora.com/How-do-I-play-a-video-in-Android-with-zero-volume-while-simultaneously-playing-music-using-another-MP3-player-app-at-full-volume