Im not completely shure yet but It seems like Pianoteq 4 is causing the freezes Im experiencing in Pro Tools 10.x.
Updating to Pianoteq 4 version 4.0.2 and disabling multicore rendering seems to have weed out the freezes in Pro Tools.
Apparently multicore rendering in Pianoteq 4 can steal important CPU resources from Pro Tools causing it to freez/crash.
http://www.forum-pianoteq.com/viewtopic.php?id=2268
Pianoteq forum admin says this is a Pro Tools problem. Is this correct ?