Covering 2 things here.
First of all the 75% rule is fricken awesome. Everything flows like water. I did a dance and techno list and before I knew it 3 hours passed by and I was mixing 1 minute or more of each song (don't know if that's a good practice but it sounded like a well tuned machine). Sometimes I dropped as low 60% to give a large crescendo effect because at that level you could only hear the highs from some songs.
2nd: When recording on same hard drive as program is ran but different than music collection (eSATA external drive) about 30 to 45 minutes into mix I get a crack or pop from program and within 10 to 15 minutes later it's so bad I can't make out the music so I stop recording and the music at same time and then I restarted right off where I was in the mix.
Is this an effect of recording on the hard drive the program is running on?
My specs are in my signature for what my computer is running. The eSATA drives works as though it should on an ASUS (2 weeks of headaches to find out it was one small switch in the BIOS; DISCLAIMER: do the research when messing with the BIOS because one wrong move in your BIOS will kill your computer. I speak from personal knowledge
)
I got a spare external hard drive and a PCI-E Firewire card I can knock some cobwebs off and give it a test run. I will share my findings within a day or two and if I don't send me a reminder to do so.