Here is what I posted on the Team 7xx thread:
"Concerning Compact Flash cards for the 788T, SD says "We recommend the use of UDMA x300 CF cards for 8+ track recording."
Well I just bought this Kingston 32GB CF and it's not a UDMA card and it's rated for only 133x
http://www.newegg.com/Product/Product.aspx?Item=N82E16820134901Nevertheless, I was interested to see if it fast enough to record at high sample rates. Recording 8 channels of 24/96 kHz works out to 2.2 MB/s.
Running a speed test on the above CF resulted in a rate of 4.9 MB/s; fast enough in theory. I recorded about 3.5 hours of 8 channel 24/96 without a hitch, so it seems fast enough in practice also."
I also own a 702 and a 16GB A-Data "Speedy" CF card. Here's what I get when I run the drive speed test on the 16GB A-Data card used as an internal CF:
702: 5.4 MB/s
788T: 7.0 MB/s
Those above speeds should be fast enough for 8(24/96) or 4(24/192) recording. Is your card almost full? Is it fragmented? Maybe if you defrag or format the card you will stop getting the speed warnings. However, I have never gotten slow drive warnings on either of my 7xx boxes so I have not had to deal with this problem.