8.6 crash/freeze/address error
 

Can anyone offer some advice on this:

I am often getting strange midi crashes where Logic stops ("address error" with a bomb), says to "try and save song"; then totally freezes; MAC must be re-set to restart.

g4 400 yosemite - 192 mb ram - os 8.6
logic 4.1.3
motu midi express xt usb

Maybe extensions related? RAM allocated to Logic? I already tried the Logic site but thought some of you Logic users could help.

Thanks