Hello Iain!
Only one small thought. when you use the Zoom as a standalone, there seems
to be a blockage, when recording and uing the speaker for playback. Have you
tried plugging in headphones while using the h4n in full duplex? Othen than
that, No ideas. I have one for the moment, but I only used it once for full
duplex and I remember we did a bit of trickery, but that may have been due to
the fact, that we had no JACK.
Warm regards
Julien
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