Problems With Alsa In-device

Hi all.

I got a very nasty problem with my setup under Ubuntu with RT-Kernel.

So, if i leave the leave the “In”-Device in the Audiopreferences empty, everything runs smooth. I can even go down to a latency of 2.7 ms without any problems.

Now, if i pick “hw0:0 ADC Capture/Standard PCM Playback” from the Dropdown-Menu, the sound starts to crackle even with a buffer of 85,3 ms.

so low latency = fast crackle, big lantency = slow crackle ( at 85.3 ms it sounds like my songs are played on a vinyl-record )

If i pick “Mix-Capture” there comes an error " Alsa: SetupHCW Parameters failed "

If i choose “Multichannel Capture” i got the same crackles as with the Standard Playback.

Any suggestions for this ? Cause i cant use my line-in now to record some stuff into renoise.

Thanks in forward.

I could be wrong here cos im going back some years… (i think it was actually an ISA slot back then - or maybe not)
I had a soundblaster live… i had a similar problem.
It was my first PC back in 1998 - i rang up Steinbergs UK helpline.

The problem was that the card is not a fully functioning ‘full duplex’ sound card.
So when the inputs were ‘turned on’ any audio playings sample rate or bit depth dropped considerably. (don’t know which)

however - any audio you record whilst the outputs sound crackly should be fine when you turn the inputs off after recording.

So its still usable - particulary if your using a mixing desk to monitor any externally sequenced gear until you sample/record it.

Another problem with the card is that its internal audio processing clock was fixed at 48khz… so if your renoise project is 44.1khz… it does a rather poor sample rate conversion at the output stage thats either handed back to the software in recording, or to the outputs on playback. Si i suggest working at 48khz and converting by some other means when the tune is rendered/mixed down.
Also a quick check on wiki! says that the front and rear outputs are out of phase - so make sure you use the front outputs or your kick will be sucking rather than pushing.
I can’t remember any more on the matter other than that i soon changed the sound card. (it was a useful spare a few times though)
Its quite an old card but those latencies are rather cool.

Its quite usable if your skint :unsure:

I know some m-audio cards work well with linux. For the price they’re great i think.

thanks for your post.

Although i have Dual - Boot running with Ubuntu/WinXP.

Im running kx-drivers with ASIO on xp and theres all running flawless. So i think it must be some kind of “Buffer-Things” in the ALSA Configuration maybe , or some Bug in Renoise-Linux version or i dont know.

And yes, my configuration is running @ 48khz already.

Have you tried to set the number of “periods” to 3 in Renoises audio preferneces. Some drivers need this to work correctly. You could also try if using Alsa full-duplex with jack works for you.