The Logic Off Topic list

Hi

I'm running my guitar through a Line 6 Pod XT into Logic 6. The 
signal is routed from the SPDIF out into the sequencer via the usual 
audio/MIDI interface. Now, I always thought that, with digital, a 
byte is a byte and what you put out gets put in? However, it turns 
out that the Pod has a *variable* digital out, which can result in 
some pretty horrible digital distortion..or am I doing something 
wrong at the Logic end. Answers to the latter, and an explanation as 
to how a digital signal can vary in amplitude would be much 
appreciated.

Thanks

Nic