flashing AT and some bugs?

I was approaching SJC after a double leg LGA-SLC and then SLC-SJC w/o restarting the sim and on approach the AT light flashed intermittently at first and then it flashed constantly. The AT was very sluggish, in fact so much so I had to disconnect. I also attempted to disconnect the AP and it would not disconnect with my x key. I had to manually disconnect it with the switch. Interestingly enough I had the cmd "A" fail on the leg from LGA to SLC (real service based failure) so I was on "B" for the rest of the time. Could this be a PMDG creative airplane fluke in the electronics, related to the other ASP failure or might this be a bug? This thing is so realistic I cannot tell sometimes so I though I might ask.