Airport Express "local clock" issue?

Several questions:
Does the upgrade for the AE help its clocking?
What is Airfoil?
I just use whatever my Imac comes with to talk to the AE. When trying this, I don't know if you'd call it a dropout or not, but the music would get very 'glassy' and harsh. just for a few seconds, and not regularly. My DAC was losing lock, according to what I could find out.

Is the upgrade for me? The idea of all my CDs on confuser, wireless to stereo and a decent DAC is too good to give up!

Kij,
Thanks for answer....and more info to be stuck in my 'buffer'.
Problem with my system is NOT the 'gap' between tunes. Stereo will simply produce a glassy, nearly fingernails on chalkboard screechy sound at random thruout play.
1. happens on ALAC or MP3 at any bitrate
2. AE plugged into CA840c to be used in DAC mode.
3. Error correction at burn to confuser does NOT effect outcome.
4. Using earbuds on AE is perfect. At least for my crumby earbuds!
5. Error does not repeat at same place when replaying tune. Always at a different spot.

CA sent me the software UPGRADE which they claim (can't remember) fixes or mitigates the problem... I'm chicken since I have to connect the player to a computer, using a null-modem serial cable. Dealer? They want to CHARGE me for this 'service'.

Null modem serial cable is needed up update the CA840c player.

The AE apparently has enough built in clock instability....jitter? that the CA simply doesn't like it. I have heard a similar sheen.....a couple times, come from my DishNetwork receiver going optical to the SAME CA player.

AE to DAC null modem? on an optical line? CA player has NO USB and besides, the USB on the AE is dedicated to printer use.

I hope the DACMagic doesn't have the same....issue, or the buyers of that guy are in for a nasty surprise.

I have the correct serial null modem cable, the directions and all the goodies, but am simply CHICKEN to hook it up and 'go for it'.
If I turn my CA player into a doorstop, I'll really be pissed.

Vinkim,
I'm just getting back to this thread.
Call CA tech support and see if there is a software update for your DacMagic.

My CA player, the 840c, simply doesn't like the optical output of the AE and does worse than skip. It emits a very harsh, glassy noise which is very hard on the ears.
My CA player simply does not like the poor clocking of the AE.

As I think about this, I believe the OPs problem is related to a network issue where the network 'wakes up' as it sees a signal. I don't know if the problem happens at the start of EVERY song.....

No harm / No foul.

I have a system problem right now that I'm working and may post If I don't figure it out.

I maybe, and probably AM wrong about your system, but going to CA tech support can't hurt. Maybe they've had this issue before?