FW erroneously flags processes trying to access protected COM interfaces/memory

Acer Aspire V5-531 laptop (Intel Pentium 967 1.3GHz, 4GB RAM)
Win7 SP1 x86 (32 bit)
Avast Free AV

Comodo FW is erroneously flagging key (and presumably what should be trusted) processes trying to access protected COM interfaces / memory. This only happens soon after boot (within a couple of minutes or so). It only happens every so often (typically once every 7 - 14 days). I say key processes - see the example attached igfxpers.exe

Initially I started allowing these to go through, but one process after another was being reported. Fortunately I make frequent images of the system partition and have been readily able to restore to a recent image and then go forward again (until the nex time the issue arises).

Deciding to investigate a little further, today, when the issue arose (first time in a couple of weeks) I just restarted the laptop when the first process was reported by Comodo (as in the screen grab attached). After restart everything was fine. The Comodo logs showed thatthe report had been made, but not taken any further. I checked the system Event logs (Event Viewer) and could see nothing untoward at all.

To me it all suggests some sort of timing issue (to do with the start up and interaction of Comodo processes).

BTW I have a very similar configuration on my desktop (but that has an i3-3240 3.4GHz and much faster disk), and no problems at all there.

Any ideas / suggestions?