Jim,
Your products have been great AND great bang for the buck - bugle, clarinet, frykleaner - and I've decided to jump into an ibook g4/itunes based music server so now I'm headed for the Chime.
Having experienced the digikey ever changing parts availability, I thought that I'd GA and check. Here are the problems encountered:
Part# Problem Suitable Substitute?
1. 478-2446-nd minimum not met 478-3162-nd
2. 478-2479-nd minimum not met 478-3195-nd
3. f975-nd minimum not met F2702-nd
4. NJM78m08fa obsolete UA78m08ckc
5. AE1303-nd obsolete AE9933-nd
Couple of other things -
6. Would there be any benefit in upgrading the USB jack? I guess that I've found that exterior connections tend to be important.
7. Along the same lines....I see that you include recommended upgrades as the coupling caps, power bypass caps and rca jacks. Is there anything else that you'd recommend for upgrades? A few extra dollars can often yield good results but sometimes it's just a few extra dollars so advice is good.

8. Your pre-loaded parts list doesn't seem to include M8702. Easy for me to add. Just letting you know.
Thanks for all your help.