Hello all,
I had the exact same problem. I figured it wasn't the PMDG 777, but I was still trying to figure out what was happening (it only happened with the 777). I then tried the DPC latency checker. Sure enough, when running the 777, I saw an issue (Windows 7 was trying to use the wrong audio driver, possibly due to the new 777 sound files) . I went into the device manager and noticed that some abandoned sound card drivers had somehow become enabled again. Anyway, I disabled all of the NVIDIA audio drivers and kept my Sound Blaster driver enabled. This has solved my problem. Also, I had a 4 gig DIMM go bad (blue screens etc) previously and am now running on only 4 gig of RAM. I can definitely see why a minimum of 8 gigs is recommended (I think though that I'll take it all the way up to 16 gig-- might save me some headaches down the road. Thanks PMDG for a great product!