MKVToolnix FP ?

https://www.virustotal.com/en/file/752c1ac05504dd65dabad66f35f6b3af6323ca0f0a2aa8116a246538086a609f/analysis/1423767247/

MKVToolnix 7.6.0

http://www.videohelp.com/tools/MKVtoolnix

Everything is fine with previous version.

i guess you have reported it https://support.avast.com/ → avast virus lab

I sent it to the lab from Virus Chest,but I don’t know if it worked since I
didn’t see some confirmation or something.
I rarely use Virus Chest.