The Grand 3/Logic noiseburst

I have a recurring problem which makes the Grand 3 almost unuseable.
If i have TG3 open in Logic, after a short while when i play or record on any other armed track It causes a very loud white noise burst-this can be stopped by arming the TG3 track-
This problem occurs if the session is large or small, so i don’t think it is a memory issue.
If i take TG3 out of the session, the problem does not reoccur.
Has anyone else experienced this and if so is there a fix-
I have not had any luck contacting Steinberg directly.
I am using a Mac quadcore 2.2.26 with 16gb ram-
Logic version 9.1.6


This looks as if The Grand 3 (I only have the SE version) generally seems to have problems with Apple’s AU format.

I use MainStage 2 and play my virtual instruments such as Kontakt, Halion Sonic, VB3 (organ), Lounge Lizard etc.

Unfortunately The Grand 3 SE doesn’t occur at all in MainStage.