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sm4tik

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From: Finland, Jyväskylä

Registered: 2006-11-05

Posts: 248

Website

[Unsolvable?] M-Audio Delta 66 sound distortion

I've been setting up my new computer and have been fighting with my m-audio delta 66 for the whole day. No matter what I've tried, the output is still distorted (haven't even tried recording yet). This far I've been trying it with alsa (and jack using alsa.. with an xrun every two or so seconds). From what I've gathered I suspect it's because it's a pci card and new motherboards don't have native pci support, but some chip that connects pci to the pci express bus. My mobo is an Asus A88XM-plus.
Does anyone have any ideas how I might get it working or should I just mark the thread as "impossible to solve" right away? Please ask for any logs/config files etc. if you think they're of any help tracing the problem! Thanks.

Last edited by sm4tik (2014-11-17 07:39:36)

sm4tik

Member

From: Finland, Jyväskylä

Registered: 2006-11-05

Posts: 248

Website

Re: [Unsolvable?] M-Audio Delta 66 sound distortion

Digging a bit deeper, I read through the pro audio wiki page and found out that there's no

/proc/asound/card2/codec#0

for the card to check the supported sample rate and bit depth (although I do know what they are). I've no idea whether this mkes any difference, just something I noticed.

Edit: ..hmm, I wonder if this would be related to the distortion as the card only supports 24bit audio but it seems to me the card is somehow configured to output 32bit and I've found no way of changing it

maatto@maattopiste % cat /proc/asound/card2/pcm0p/sub0/hw_params                      ~
access: MMAP_INTERLEAVED
format: S32_LE
subformat: STD
channels: 10
rate: 48000 (48000/1)
period_size: 256
buffer_size: 512
maatto@maattopiste % cat /proc/asound/card2/pcm0c/sub0/hw_params                      ~
access: MMAP_INTERLEAVED
format: S32_LE
subformat: STD
channels: 12
rate: 48000 (48000/1)
period_size: 256

That's the outputs after starting jack for testing.

Last edited by sm4tik (2014-11-14 09:25:09)

satanselbow

Member

Registered: 2011-06-15

Posts: 538

Re: [Unsolvable?] M-Audio Delta 66 sound distortion

Making the wildly reckless assumption that you are running jack / pulseaudio / alsa ... have a poke about in alsamixer - my onboard card had a "boost" enabled by default (in and out) when I was setting up jack ... I wouldn't have thought 32bit would present a problem as it would downsample to whatever it can handle...

sm4tik

Member

From: Finland, Jyväskylä

Registered: 2006-11-05

Posts: 248

Website

Re: [Unsolvable?] M-Audio Delta 66 sound distortion

I'm away for the weekend so further testing has to wait. There's no boost available in mixer settings and to be more exact, the distortion is more like a digital version of a warped old LP that's been heavily abused. It's not like the sound is getting overdriven.
I  also realized that arecord was complaining about S32_LE being the only supported format when I was testing it. That would make no sense if the card was properly recognized as a 24bit. To me it seems and sounds like the card is currently forced to output 32bit audio which it obviously can't handle.

sm4tik

Member

From: Finland, Jyväskylä

Registered: 2006-11-05

Posts: 248

Website

Re: [Unsolvable?] M-Audio Delta 66 sound distortion

I'm kinda back to where I started from. Poking around the net just confirmed S32_LE being normal so I'm giving up for now and and blaming it on the newer mobos handling of PCI bus. I'll just put the card to my old pc lying around in the cupboard and see what happens. Any further info or help will still be appreciated, though I doubt I'll ever get this combo working.