ALSA CDrom Problems

[jaduff]

Lo
Sorry if this has already been covered somewhere, but I couldn't find it.

I have a cdrom which plays cd's fine through analogue. However, I have a sblive! value card that has 4 speakers attatched, and I want to use all, when I try to use alsaplayer to play the cd I get really bad stuttering. I get the same if I use the xmms-cdread plugin to play digitally through alsa. If I'm running KDE and tell xmms-cdread to play to arts, which then plays to alsa, it works fine.

What have I done wrong, and what can I do to get alsa to play cds properly without stuttering or going through arts first?

I've tried with the current stable alsa-driver (0.9.2) and the ~x86 (0.9.4-r1) with alsaplayer stable (0.99.73) and ~x86 (0.99.75) to no avail.

This has remained a consistant problem across multiple kernel upgrades.

Thanks for any help
_________________
--James (Dugite)

[Regor]

One thing that comes to mind is DMA. If DMA isn't enabled you may not be getting enough bandwidth on your bus to allow stutter-free audio.

Take a look at the contents of /proc/ide/hdX/settings - substituting your CD drive for hdX - and make sure that using_dma is set to "1".

If it isn't, check your kernel config to make sure you're compiling in support for your chipset in "ATA/IDE..."->"ATA and ATAPI Block devices". If that's in (not as module) then you should get DMA on the bus.

If that's not the problem, then I dunno
_________________
Sometimes the appropriate response to reality is to go insane.
-Philip K. Dick, Valis

[jaduff]

Ok thanks for that, as for using_dma, yes thats set to 1, for the ata/ide stuff I'm using scsi emulation on it and on a separate burner, on it because the burner software wants to read from only scsi from what I can remember.

I have my ide chipset support stuff compiled into the kernel, its pIIx or something along those lines...

I added ide/atapi support as a test, and still no results... could the scsi emulation be getting in the way?

Thanks
_________________
--James (Dugite)

[jaduff]

I found a solution, and I have a suspicion to what the problem was, although I'm not certain.

When I play the cd's digitally through my dvd player (slave on the same ide line), there is no skipping, the only thing I can see that could cause this difference is that the dvd player is NOT connected via an analogue cable to the sound card!

I suspect that the cd was being played to two destinations at once, meaning either than the cd was being read twice... or that the sound card was being read the same data at twice, but out of sync.

I'm gonna play around and see what I can some up with, but a solution never the less!

Thanks for you help
_________________
--James (Dugite)

[kf0yn]

It sounds like you have both the analog input for the CD and the digital input turned on in the mixer. That'll certainly create some interesting effects.