Crackles - ok to change power settings?

[Skyline]

I use Sonar with a Delta66 interface and occasionally get the dreaded low level 'crackle' or 'sizzle' noise on recorded tracks. It's such an extremely elusive nuisance, as evidenced by the enormous number of threads on various forums. In my case I can sometimes get rid of it by exiting and re-opening Sonar (why should that change anything??), or by changing something in Sonar's audio settings and then changin it back again - but all that is probably co-incidence!

Although not a tech-type, I can see from the various forums that this could be related to a zillion different things from buffer and latency settings in Sonar to unplugging any LAN connections and excess USBs, but I came across some other advice which I wanted to check here first.

Some advocate changing the BIOS power management settings, specifically changing Speedstep to 'disable' and the same for C1E. Is it ok to do this on my 3XS? And what about 'CPU C State'? (enabled on mine).
Are there any other things that might be causing the crackle in a 3XS/Delta66/Sonar setup?

Thanks in advance for any helpful suggestions!

John
PS:
Link to MAudio FAQ ref. power management.