I'd have to say my biggest annoyance was hardware functionality. Never had a problem with Hucards, but damn the cd units suck.
I had a cd add-on bitd, and remember it not working, unless I placed a heavy book on top of the cd unit! Wtf? (And the laser...don't get me started on that)
System worked for years that way, eventually stopped tho, and I ungraded to a duo, which have to this day, had the sound issue that I got fixed, and flimsy hucard doors.
Doesn't matter what happens tho, I will always love this system.