Maudio Profire610, Compatibility Options

[Dee1]

I'm running Mac 10.4.1 with a 1.5 Ghz Processor with 1ghz of ram with DP4. Just bought a MAudio Profire610 - not using the HD output. They (Guitar Center) said it should be compatible. So here's my problem. Downloaded the latest driver from Maudio, installed it, went under system preferences and launched it. I can hear my Korg Triton rack, even when DP isn't launched. When I launch DP, I get an audio signal, but no audio signal from the recording meter. When I hit play or record DP crashes. Is this most likely a DP problem that can be fixed with an upgrade ? or a compatiblity problem ? Or my computer needs faster memory ? I'll go Motu Interface if anyone has suggestions. Switching is not a problem. Should I save all my packing material ? I'm tired of playing tech man and just want to lay down some tracks without using Garage Band. I know DP pretty good. Sorry so long, it's late, and I'm tired. Thanks in advance.
Dee