[linux-audio-user] clicks with video activity

Hello, I'm getting clicks in the audio using jack when there is video activity (i.e. audio software that displays meters like Rezound, when muse refreshes the display at playing and following the cursor, when minimizing and maximizing windows, etc). If I increase the latency they seem to stop. What could be causing this? Here there are some details of my system: Asus P4P800Deluxe Pentium 4HT 2.8 ghz 1 gig ram M-Audio Audiophile Agnula Linux with kernel 2.6.12 (with preemption) This is my cat /proc/interrupts hector@demudi:~$ cat /proc/interrupts CPU0 0: 3167206 IO-APIC-edge timer 0/67206 1: 601 IO-APIC-edge i8042 0/601 7: 0 IO-APIC-edge parport0 0/0 9: 0 IO-APIC-level acpi 0/0 14: 20770 IO-APIC-edge ide0 0/20769 15: 43 IO-APIC-edge ide1 0/41 177: 187389 IO-APIC-level uhci_hcd:usb1, radeon@pci:0000:01:00.0 0/87389185: 205449 IO-APIC-level uhci_hcd:usb2 0/5449 193: 3 IO-APIC-level ehci_hcd:usb3 0/3 201: 21466 IO-APIC-level Intel ICH5 0/21466 209: 3 IO-APIC-level ohci1394 0/3 217: 35511 IO-APIC-level SysKonnect SK-98xx 0/35511 225: 1696593 IO-APIC-level ICE1712 0/96593 NMI: 0 LOC: 3167251 ERR: 0 MIS: 0 I have jack set to 128 frames, 2 periods and 44100 sample rate. The video card is a Radeon 7000. As you can see my audio card is in the last IRQ (225: 1696593 IO-APIC-level ICE1712 0/96593) so I was wondering if this is the cause. I tried to set a higher priority using chrt -f -p 99 `pidof "IRQ 225"` but it didn't fix anything. I remember having the same problem long time ago in windows when I had an Intel motherboard and I was using the built-in video card. The problem disappeared when I installed a new AGP card. Thank you! Hector