[LAU] disappointing experience with firewire

hi, this is no complaint (!) about anything, just to reflect over my yesterday's exerience with a newly purchased Focusrite Saffire Pro10, connected via Belkin PCMCIA Firewirecard to my Lenovo R61 - the FW Chip in this Laptop is one of those crappy Ricoh parts, I tried this, too, but as expected it just didn't work... So I compiled the ffado Release Candidate, afterwards compiled the actual Jack 0.116.1 and finally got things running. Compared to my Lexicon Omega Studio USB Device the performance of that FW assembly (don't want to blame a single device of that chain) just was disappointing, already in idlemode without any clients open the jackserver showed a workload of roughly 5% (128 frames/3 periods), while my Lexicon produces between 0.5 to 1% (128 frames/2 periods). Opening Ardour and just replaying one of my sessions produced glitches where only a strong hiss could be heard. (The session itself caused a workload of less than 20%.) - I remember having had those hiss glitches in my early days in 2005 with the MAudio Transit USB and Kernel 2.6.11 - I never expected them coming back some day... *lol* I then had a look on my interrupts and had to notice the FW Card sharing it's interrupt (no 16) with the Nwidia Graficscard - so I might have found the culprit - or not? - I don't know... :-((( I tried to change the pci settings in the bios - no success. Now my question to those who also tried firewire audio: was it a success story for you from the beginning or did anybody make similar experiences and how did you proceed further? thanks for your attention Susanne