Maybe there is some dirt in usb port, try to clean it.

In my case gapless doesn't work, but as far as i know, it depends on CUE. About the number of files - never had problems with that - i don't use play lists.

The latest is 1.41. Its stable and OK. tsh-corp.com/home/?page_id=26

I've tried. No change in sound noticed.

Here is a new firmware 1.41 for Aune M2 - http://tsh-corp.com/home/?page_id=26. Thank's to a Damned1 from Russian forum.

I'm using Aune M2 Pro with MSR7. Previously i had Hidizs AP100, but M2 Pro is much more preferable, it has darker sound and highs are less sibilant.

Foams, fabric, custom pads won't remove sibilant from sound, the will only remove harshness a bit. Sibilance is a matter of record quality. MSR-7 is very critical to record quality. For reducing sibilance try to google "DeEsser".

Quote: You may insert cotton pads (divided for 2) under the pads. Don't forget to remove cotton from pads. http://player.ru/attachment.php?attachmentid=160112&d=1471759256

I've never listened to them, sorry.

Personally, i prefer MSR7 to M50X for rock and metall.

Can you describe changes?