[LAU] clicks in sound when running dual core

Hi folks, Been reinstalling my studio computer these last few weeks. Moving to 64 bit and dual core.. or so I thought. As it turns out I have found that my system is unable to run jack reliably while using dual core. I use MusE as sequencer and it's especially evident there but I believe I have noticed it with other applications. The thing that happens is that I get random clicks in both input and output. If I start the computer and add maxcpus=1 to the kernel line all seems ok. Thinking back I realize that I stumbled on this problem on the last rebuild some years ago but ended up running single core without investigating why this was. I thought I would at least throw this out here now, google seems to know nothing about this issue. Anyone else have experienced anything similar or is my hardware faulty? (AMD64X2 based) Regards, Robert