I read:

I've got an M-Audio Quattro set up on my RedHat 8.0 system and I've been having trouble using PD + jack and four channels. When I start jack with the hw driver, the first two channels (in and out) bind fine in PD. However, when I run jack using the q4b driver (4 ins, 4 outs) the outputs bind properly. Although the connections look fine in QJackConnect, with pd's outs connecting to my quattro's two outs in the proper way, I only can get sound out of PD's second output. And furthermore, the sound I get out of the second output is coming out of _all_four_ of my quattro outs. What's going on here? Any ideas?

I suspect that this is a bug in deve_0_36 I have the same problem when I use pd with more than 2 channels on my builtin card 1st channel is silent, 2nd channel plays on both channels.

just to make sure that it's not jack's fault, what version are you using ?

regards,

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