How do I repair my Miracle?

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How do I repair my Miracle?
by Dwedit on 2007-11-14 (#28260)
I have a mostly working Miracle Piano Teaching System keyboard. The left audio channel is very sporadic. I can get the left channel to work briefly if I turn the power on and off, then goes away after I press any face buttons, occasionally it stays for a few minutes.
It's not just the speakers, since the left channel of the headphone jack also goes out at the same time. Haven't tried the RCA audio jacks.

It also occasionally plays some soft low frequency white noise for a second or two.

Any ideas?

by sepi on 2007-11-14 (#28262)
Check all electrolytic capasitors from amplifier block. They tend to act sporadically, if they have dried up or exhausted. If you find any suspicious caps replace them, but use higher voltage spec.

I assume that the speaker amplifier is shared from headphone, that would explain why the headphones go out too.