Anyone else own the Fender P-Bass controller?
 

I went to plug it in to my 360 to play some Smash Hits under Bass career. It was recognised as a regular controller, I guess, because I had the mic symbol under my name and a warning that I needed to plug a microphone in before I can continue.

Is the P-Bass controller incompatible with Guitar Hero titles, is this just some weird anomaly, or what?

probably not compatible.

Which one is it?

If you're talking about this one, then Amazon's product description lists it as not compatible with Guitar Hero.

http://ecx.images-amazon.com/images/...PL._SS400_.jpg

The product description predates RB instruments being compatible with GH anyway.

Needless to say, it wasn't the reason I bought it.

Followup, on the off chance anyone else was actually wondering (Odds: 1 in 42,000,000):

The solution is to switch the switch on the back from RB2 to RB1. Then it functions on GHWT/SH.

Which I would have tried, had I even remembered there was such a switch.

unless you can play video games with it, GTFO.