7.1 surround card crackling

chammes's icon

I am using a PC running windows 7 that has a 7.1 surround card and five dual output video cards installed. When i try do run a simple max patch using 7 different oscillators it crackles and skips. This so far only happens with max, not when playing mp3s or when running ableton live, or when doing the windows sound test.

The patch I used to test this is simple, with 7 cycle~ objects connected to +~ objects, connected to a dac~ with 7 output channels. The other problem is that the dac only recognises 5 of the 8 possible outputs. The PC has a feature to automatically recognise how many speakers are plugged in, and it's set up for 7.1 surround.

Some research suggests that it could have something to do with the heavy processing being done by the Nvidia cards and the Creative Soundblaster sound cards (this came from the Creative website). But I don't understand why it only happens with max/msp.

THe sound card is a Creative Soundblaster X-Fi Xtreme. The graphics cards are Nvidia GeForce GTS 450 graphics cards. These outputs are connected to ten projectors at 1024 x 768.

I can't find any information in the forums that can help me account for this problem. I thank you in advance for you help.

dtr's icon

what's your cpu load (in %) when this happens?

chammes's icon

Sorry for the very late reply. I don't recall what the CPU load was, but it wasn't very high. I suspect a driver-related issue, but I have no experience troubleshooting a 7.1 card.

I ended up returning the Soundblaster card and purchasing an ESI Gigaport HD with 8 outputs, and now it's running smoothly. I know that doesn't help solve the previous problem, but it's a way around it.