What VOR were you tracking? Maybe you had the wrong frequency programmed into the NAV radio causing you to be going off course rather than tracking the correct VOR. That's the only thing I can really think that would cause that to happen. Unless, like you say, the HSI is messed up. I haven't seen anyone else mention having this problem.

As for the ATC. I was just having a gripe about it. I did an IFR flight yesterday, and the ATC had been driving me nuts during the flight. :D

Mark