digital i/o...working? Not working?

[ThomCat]

Attn Tech Support/concerned DUC'ers:

Should you not be able to test your digital i/o on a Digi 001 by using the provided ADAT cable to loop the output back into a second input (as long as you take care not to route the digital input back into a feedback loop)? Or how about testing the SPDIF i/o using one simple high quality RCA patch cord?

Using a patch seems to work for testing the analog ins and outs, but I'm hoping to fly tracks in and out digitally pretty soon, and loopback testing the i/o in this way seems to yield no sound throughput whatsoever. Am I doing something wrong? (or stupid?)

I admit I haven't tried using PTLE software to configure the ports other than the basic driver setup screen, but should I have to? Shouldn't the digital ins/outs be active all of the time anyway?

I use Logic/DIO driver and have no desire to go back to PTLE again (no offense) but there seems to be little in the manuals (about 8 lbs of material on PTLE to about 3 pages on the hardware, thankyouverymuch) to support using PTLE and digital i/o and virtually nothing to support using third-party software (just a hardware ADAT).

I'm stumped. Please help. Anybody.

Incidentally you might be happy to hear that two trips through the 001 at 24 bit (into inputs 3/4, out outputs 3/4, directly back into 7/8, and then back out 7/8) which should be two complete sequential trips through the adc/dac's yielded no sonic degradation that I could hear.