So I've been trying to unravel TMA-1's signal-not-found issues (as detailed in another thread), and I found something interesting.   TL;DR: the OEM TI cassette cable tape-audio-1-input jack is wired incorrectly for equipment available now. Leave pin 9 floating and run pin 3 to CS1 plug sleeve and things magically work.   Under most circumstances, when wired straight into either the headphone or line-in jack, the signal heard from the TI speaker is low. Really, really low. Much, much lower