[SOLVED] problems with 1818vsl

[tatch]

I was using my 1818vsl with both a macbook and an archtop for a while (3.12) without any issues. I got a new laptop recently and put ubuntu 12.04.4 on it, installing the kxstudio repos on top as well as a lowlatency kernel ( 3.8 ). The first time I connected my 1818vsl it was in the 3.8 generic kernel but it worked without any significant issues until I plugged in my bass, which sounded incredibly distorted and full of noise. I plugged the bass into the other ports and it sounded the same so I restarted my computer into 3.8-lowlatency; when I started up JACK there was simply no output at all.

I verified the inputs are working by setting the inputs to 1818vsl and outputs to onboard card but I can't figure out why the 1818vsl isn't outputting anything. I tested the 1818 on my archtop again to make sure i didn't somehow bust it and it still works. I tried running it on 3.5-lowlatency and 3.11-lowlatency but none of them worked (i couldn't even reach lightdm with 3.2 since I guess I need older driver or something). Does this sound familiar to anyone? I'd greatly appreciate help.

edit: actually I remember there actually is another issue, this entire time I've been getting a huge number of xruns, even with 44100/1024/3. This is quite a nice laptop so I'm really surprised and annoyed. I'm positive it can do better than that.

[tatch]

I also find it strange how even though I can't output audio to the 1818vsl I can still hear the popping of every xrun which happens every 3 seconds...

another observation: when I use only the inputs of the 1818vsl and use my laptop output, I can run it at 48khz/512 with a few plugins and midi and i've only gotten 15 xruns in the past 3-4 hours.

[ffisher]

I have an 1818VSL, which was working flawlessly for about 2 years in Ubuntu 12.04. I recently bought a new computer and suddenly it has crackling sounds and xruns on a faster processor.

I did a little research, and the problem is xchi-hda, the usb 3.0 driver in newer Linux kernels. It will treat the 1818VSL as a usb 3.0 device even though it is a usb 2.0 device. You want the kernel to use ehci-hda, the usb 2.0 driver, rather than xhci-hda. Unfortunately, in Ubuntu these are built permanently into the kernel rather than set up as modules. To get it working, you have to either:

1. Disable usb 3.0 in the BIOS or
2. If your BIOS does not have this option, compile a new kernel with xhci-hda and ehci-hda enabled as modules. Then blacklist the xchi-hda module.

More info on that here: http://www.pcl-developers.org/xhci-hcd- ... 07949.html

I don't have the option in BIOS, and unfortunately, I'm having trouble compiling a kernel. More details here:

http://ubuntuforums.org/showthread.php?t=2214154

I hope this info is helpful to someone here. Let me know if you all make any progress.

[GMaq]

Hi,

I've found that the VSL1818 can be a quirky beast, although my machines are all too old for the USB-3 bug mentioned by ffisher I have encountered the no audio issue several times, in my experience I have shut down JACK, unplugged the USB cable, powered the VSL on and off, reconnected the USB cable and re-started JACK and voila it will work!

Secondly I have found that a Realtime kernel isn't just a nice option for these units it is almost a necessity, On a well tuned low-latency kernel 1024/3 was still yielding Xruns while the same Kernel with full RT preempt took it down to 256/3 with no Xruns which is low enough for my needs

My experience with a Scarlett 2i2 has been similar, USB Audio devices seem to respond far more significantly to RT than FireWire and PCI cards which don't really show much benefit any more...

[tatch]

ffisher, thanks for the lead, it looks very promising. I turned off XHCI preboot mode and while it still isn't working at least I've actually not gotten any xruns. I guess I'll try custom compiling a kernel like you said. Last time I compiled my own kernel I ended up rendering half of my hardware useless so I'm looking for some guides or something. GMaq, I don't quite understand how to compile a kernel with full RT preempt but hopefully I'll figure it out.

update: i followed the instructions on the linuxaudio wiki to compile an rt-kernel and also made sure to compile xhci and ehci as modules, blacklisting ehci in /etc/modprobe.d/blacklist.conf but it still doesn't work. sigh

[Broomy]

I think ffisher is right, my 1818vsl was also giving a lot of xruns when attached to my usb 3 input of my laptop. When I insert it in my usb 2 input everything is fine.
I'm using also using kxstudio.

[Broomy]

tatch,

Do you got your card working allready?

[tatch]

tatch,

Do you got your card working allready?

no, still haven't gotten it to work. I tried plugging it into a non-usb-3 port as well but it doesn't make any difference. I have noticed though that I no longer get xruns in this configuration which I guess is a good thing? Still a little disappointed that it's not working yet. Perhaps I'll try out falktx's 14.04 iso when he re-uploads it and see if it works then.

[tatch]

great news, I finally got it to work with the custom kernel. The problem was just that some of the ports were muted in alsamixer.

[Broomy]

Great!

Edit: I forgot to ask: How did you resolve the issue you had with the usb 3 input (getting Xruns)?

[tatch]

i'd like to revisit this topic because I now have a usb3.0 external HDD. disabling xhci across the system prevents me from being able to utilize the superior speeds enabled by usb3.0 so i was wondering if anyone has found a way to force linux to load the ehci driver when the 1818vsl is connected. I found this stackexchange question which could be helpful, if nobody has any definite answers I'll try to pursue this further.

[emarsk]

I now have a usb3.0 external HDD. disabling xhci across the system prevents me from being able to utilize the superior speeds enabled by usb3.0 so i was wondering if anyone has found a way to force linux to load the ehci driver when the 1818vsl is connected.

I'm in the same situation, and I tried some suggestions but the only way to get the USB audio to work properly on my laptop is to disable the USB3 in the BIOS. If I leave it enabled, then I can't modprobe -r xhci because it's in use. I'll try the route that you posted, though.