I mentioned the background noise observation.

There is a lot to be said about the power of suggestion. The high cost of audiophile equipment is based on it.

I don't think what you describe is even an analog/digital thing but rather an equipment design issue. I can clip my buttset on a POTS line, break dialtone or access quiet battery and hear just as much hiss. True, Partner does have a little digital hash riding on it but again, that's a design issue. Apparently it wasn't objectionable to the engineers who designed it. Other systems are designed differently.

Another thing to consider too is that proximity to other equipment, particularly monitors will produce the same effect.

-Hal

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