Explain "messed up".. I'm sitting at a computer very far away and really can't quite get my telepathy working enough to understand the symptoms from your description.

Hopped, rocked, stalled.. it's not quite making sense with messed up to me. Please try to be very descriptive as to when it does what and how it seems to do it.

I won't guess on pcm or tcm because typically they aren't an issue. There are many more things that can be the issue before we start talking about either of those.