Harsh noise on P2 transmissions following Vocoder change

[SimonSheehan]

Following the vocoder change, on the occasional iffy decoded transmission I will end up with a sort of Decepticon sounding awful noise. Other users noted it as well.

This is very much specific to the changed P2 vocoder - I was previously reverting that commit and could safely merge, but since the P2 files have changed a bit with some new features, I no longer can, thus the problem has become unavoidable.

I do not believe the softVocoder option is working either as it should with these changes, as having that enabled does not help. In theory, it should be reverting back to the old P2 vocoder.

f40ab20is the last good commit before this occurred. Commit 065501e is when it began.

Sound can be found in the T-R discord at this link.