[linux-audio-user] Intermitent Xruns...

[Russell Hanaghan]

On Fri, 2004-04-09 at 11:21, Mark Knecht wrote:
> Russell Hanaghan wrote:
> > On Fri, 2004-04-09 at 04:41, Florian Schmidt wrote:
> > 
> >>On Thu, 08 Apr 2004 23:35:50 -0700
> >>Russell Hanaghan <hanaghan at starband.net> wrote:
> >>
> >>
> >>>Hi,
> >>>
> >>>I have set this laptop up in a CII docking station now that houses 2
> >>>SBLive PCI cards. I have them chained with a modified .asoundrc file
> >>>that gives me 4 ins and 4 outs. I have been using Ardour as the host
> >>
> >>Hmm, do you have any possibility to make these two cards sample synced?
> >>i suppose not. therefore using them as multichannel device will fail due
> >>to clock differences..
> > 
> > 
> > I'm not actually using this setup for recording any tracks. Will it
> > still be an issue just for monitoring?
> > 
> > R~
> > 
>   If you intend to monitor out of both cards at the same time, then yes, 
> it's likely to be an issue. Each card is running from it's own clock. 
> Imagine one is running at 44101 Hz and the other is running at 44099 Hz. 
> Jack can only be in sync with one of those rates. If it syncs with the 
> fast one, then periodically the slow on will overflow. If it syncs with 
> the slow one, then periodically the fast one will run empty.
> 
> There is no way to solve this problem unless you 'sync' the two cards by 
> means outside of Alsa. I use ADAT clocking (not ADAT sync) and clocking 
> over s/pdif to sync multiple cards in multiple computers. It works 
> great...once you get it under control. The RME cards provide good 
> support for this and good software is available in both Windows and 
> Linux to see if things are in sync or just in lock.

Got it!  Makes sense now.

Somehow the "External sync" capabilities are prolly less than adequate
on 2 SBLive 5.1's that I paid a massive $19.00ec US for! :)

Can midi control do this...they both have midi ports that show in
Qjckctl?  MTC is what I'm wondering....not being a midi genius I really
dont know.

Thanks
R~
> 
> Good luck,
> Mark