H5 C1 YM AUDIO FIX

[exxos]

@PhilC Spotted this one, I had not yet checked any of the audio system out since the redesign.

Symptom is the YM audio ( I just tested the normal key click sound) fades out over several seconds. Problem is a biasing issue on the audio amp which thankfully is easy to fix.


Slap **1K of your favourite variety across the highlighted points below...

(** This was previously incorrectly listed as 100K)

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[PhilC]

@exxos Verified working for me as well, thank you

[exxos]

The above mod has been changed from 100K to 1K.

In addition a 100nF (0.1uf) ceramic type capacitor needs adding across the same resistor. This will prevent hissy / distortion when playing music. Oddly the diagnostic cartridge sound test doesn't show the issue.

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