Bad Crackle after Mixdown?

I am experiencing a bad, steady crackle in my mixdown. It is there when I use the built-in audio as my ASIO during playback as well. The mix sounds great on my Tascam US-1641. Any suggestions?

Cubase 5.5.2
MacBook
Intel Core 2 Duo
Processor Speed: 2 GHz
Tascam US-1641

Up the buffer size on your soundcard?

Configure the Tascam in core audio.

Probably in line with mashedmitten’s suggestion for a MAC, but my experience with the Tascam was on PC- I was experiencing VST limitations (latency, buffer size settings) untill I experimented with ASIO4ALL. I ran the Tascam as a choice INSIDE of ASIO4ALL and that yielded a VERY considerable improvement in performance of the mixer.
Don’t know if these settings would be applicable to a MAC, my guess is that core audio is MAC’s sister to PC audio (?)
Just thought I’d chime in with my experience in case it would help someone with the Tascam. :slight_smile: