WebUSB / Headphone connection to Espruino

I got the guys in the shop to look at it with an oscilloscope, there is definitely voltage on the line, with about 1.5v swing.

analogRead without pinMode set (i.e after a reboot):

setInterval(function () { console.log(analogRead(A5)); }, 1000);
=1
0.39795529106
0.28686961165
0.27002365148
0.42871747920
0.01000991836
0.13598840314
0.16748302433
0
0
0
0

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