Some of your problems may well be associated with the Creative Soundblaster X-FI Platinum in Windows 7. I had this soundcard installed with my updated HP Pavilion DAW last year and it took me months to iron out various problems associated with Win7 plus this card.

I found that several VSTis would not load into Win7 environment - the exe file of one was rejected by Norton Anti-Virus as a Cloud Virus. Some of these problems have been overcome. As regards to the Creative Card, I have found that the MME audio drivers were not stable but liable to crackle occasionally in Play mode and useless in record mode - even those drivers resident to the operating sytem were no improvement. I now use the Creative ASIO driver which works perfectly for Play and record via the Soundcard. Unfortuately, render with a few of the VSTis by ASIO has been ineffective as, for some reason, the VSTi Patches are removed during the process and blank Audio tracks result. On other occasions, part only of track has been produced irrespective of the highlighting.

However, for this process and the few VSTis affected, a return to the MME drivers works fine.