Originally Posted By: EFalardeau
The humming is most likely a ground loop. Did you loosen up the ground screw at the back of the 500?
Also, when did you back it? Mine does not have an auto-off; just the 12V trigger.


With the EP600 I have in our theater setup there was always a humm, Its not that bad so I never really played around with it to try and fix it, I never thought to try the chassis ground screw. I went and unscrwed it a couple turns and now the hum is completely gone! thanks for reminding me of this feature!

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