Is anyone having problems with OS 10.5.7 update?

Question

I have a Tascam US-122 (older unit), and all was fine until the OS 10.5.7 update. Now, I get a signal from my US-122 going in that I can see on the system prefs panel, but no sound coming out of my monitors. ALL other audio devices DO come out of the monitors just fine.
I have looked at every setting possible, and nothing.

Answer 1

Yes, the US-122 is a usb interface. I have been using it for several years now.
I have had no problems until this last OS update, which also included an iTunes update that I have heard folks are having burning problems with.
I can SEE the signal going in (in the sys prefs meters), as well as in LE's meters, but no sound comes out of my monitors. Yet I CAN play songs in iTunes and pre-recorded tracks in LE7 and GB, without problems at all, as well as any other audio from online sources and from the OS, like alerts, etc. It is only audio straight from the US-122 that does not make a sound.
I find it so odd that the OS Sys prefs show a signal, yet no sound is present, while all other apps produce sound as usual.
I have repaired permissions, and have reset SOUND and AUDIO/MIDI setting severals times.
I USED to be able to play guitar through my Vox ToneLab, connected directly to the US-122 into the Mac, whether I was using LE7 or GB or neither. Now I get NOTHING from it at all (aside from the OS meters), no matter what.
I'd suspect a cable if not for the signal in the meters, and the sound from every other audio app, including pre-recorded LE7 & GB stuff.
I have had minor problems in the past, but never anything like this.