[LAU] Cracks while using Audiophile 2496

Hi, I just bought an Audiophile 2496. Unfortunately, it does not work as well as I imagined. Here are the symptoms : * Simple listening (no jack, just alsa): - when I route PCM outs directly to HW outs, I here "cracks" on the right side (I don't know the precise english word to describe the noise, see below for example) - if I switch the RCA cables, the cracks change side - when I route the digital mix to HW out, I don't hear cracks * Recording (jack, no xruns): - I can record my guitar (I use the RCA analog in) - I still hear the cracks while I play and in the recorded sound (example :http://manu.mindslicer.com/export.wav). These cracks are very similar to what I hear when I listen music without jack (with PCM out -> HW out). I tried with different sets of cables and headphones. What do you think ? From what I heard, I doubt it is a software-related problem. A lot of people use the Audiophile without problem. Moreover, switching the RCAs switches the side of the cracks. I just wanted to have your opinion before sending the card back. Could it be a configuration issue ? Is it a problem with the chair-to-keyboard interface ? Thanks in advance for all the advices you can give me. Cheers, Manu Conf: ------- Arch Linux 64 bits (Intel Core i5, 4 Gb RAM) M-Audio Audiophile 2496 alsa 1.0.24 envy24control 0.6.0 jack2 1.9.6 qjackctl 0.3.7