Rossmaxx

I am resetting this PR and will push the new changes soon.

Looking back at dom's text wall, I realize that that is exactly what he said. I will do the changes anyway and get it to compile everywhere else and then...

I'll look at the new errors later.

All that's left now is bumping the cmake version. Waiting for #7259 for that

Would be better to have #7027 in favour of this issue.

Oversampling is gone entirely since #7228

@sakertooth close?

Oops, another misread.

should we close this one in favour of https://github.com/LMMS/lmms/issues/1911 because that one's more descriptive?

Better to consolidate, as we all agreed to move to that direction