Edmousethemouse

from the Apple Support Board: Plase check this thread on issues of the new AEx (square) when connected via toslink to a lot of different DACshttps://discussions.apple.com/message/20359523?ac_cid=tw123456#20359523

I have an alternate plan. With Airfoil Speakers you an make another Mac an AirPlay destination. I run that on a MacBook Pro that is connected to my Network (and the music files drive) via Ethernet. I use a Toslink cable from that laptop to my DAC. That bypasses the Airport Express altogether. Can anyone say if that method has any more audio integrity?

In my case all the connections are Ethernet. I wondered about the integrity of wireless and eliminated that from my chain. All of the above is probably still true but I just thought I'd mention that. I'd actually love to know if it makes a difference. (I didn't hear one when I tried wireless.)

The jitter may be inaudible between the two units but I can tell you this. The digital signal output of the newest (3rd generation really) square Airport Express cannot be maintained on my DAC that contains a Sabre chip! The DAC (Wyred4Sound DAC2) cannot hold the signal. The output drops completely at regular intervals. When I put back the 2nd generation (the "n" one) of the 'plug in the wall' Airport Express the signal remained steady. I also have a Schiit Gungnir DAC. It has a light that shows an inconsistent signal and switches to a lower resolution decoding chip if necessary. With the newest AEx, if I use Amarra or another player in conjunction with Airfoil that light is constant. When I put my original AEx back in, the warning light remains off and the DAC can operate at full resolution. It's maddening. I do have two DACs (Bryston and older Headroom) that lock on to the signal even with the newest AEx. But there are definitely differences and apparently not in favor of the newest unit in regard to jitter.