Re: [Jack-Devel] ALSA PCM multi plugin and xruns

On Tue, Dec 11, 2012 at 12:56:04PM -0600, Chris Caudle wrote:
> Probably  not a useful line of investigation, unless it can be reconciled
> with the later message from John Riggs:
> > BTW on my main system with 3 x ice1712 cards there's a
> > common clock supplying all three cards simultaneously.
> > It also shows the same xrun messages from jackd when
> > using pcm_multi.
> 
> My understanding of John's system is that he has three identical cards,
> and has physically modified the hardware so that they all operate from a
> single oscillator feeding the ice1712 chips on the cards.

Yes, description here:
http://www.jrigg.co.uk/elec/interface.html

> I don't see how
> it could apply to that system.  Possibly there is an ambiguity in that
> case with startup because of differences in reset timing to the individual
> cards, in which case the cards would be locked in frequency, but might
> have a fixed offset in the number of frames in the buffers at any
> particular time.

Interesting point.

John

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