that being said I'd try 2 things. One try going to his LV 1.25 kernel. Second I wouldn't put it on performance specially if you use the temp profile in setCPU depending on what temp you have it set to. Reason I say that is with performance is it being clocked at 1.25 almost all the time. With that being said say the temp gets to high and then it clocks down to cool to whatever setting you have set, well the voltage change with the tasks at hand and slower clock speed could be causing the freeze up.
If you don;t want to test another kernel first I'd lower the high end of your setting to 1Ghz or a notch lower and just test it. If that works out and doesn't freeze and you really want it at 1.25 install a higher voltage kernel and test it at 1.25 again. Personally tho at this time of year with ambient temps and running at 1.25Ghz and multi tasking it could just be a heat issue. Winter time I'll run mine at 1.1 or higher, but this time of year I try to stay 90Mhz of lower. And now with Froyo out you will barely notice a difference in normal daily use at the lower clock speed, IMO at least.
