Comment 2 for bug 1766750

I've just read this article:
https://askubuntu.com/questions/41348/why-can-the-volume-go-higher-than-100

where this setting below in dconf solves this problem:

dconf write com/ubuntu/sound/allow-amplified-volume false

It can be found in dconf-editor also browsing "com / ubuntu / sound" section.
Don't know whether it works in Mate or only in Ubuntu, but I hope it can help out this problem on Mate also.