Recently I came back from a trip turned on the amp and one of the speakers started generating a low pitched hum. This persisted whenever the sub is powered even when the amp is off. When I was away the system was powered on at the mains so the speakers were powered though the denon kit was powered off / on standby.
It turns out the sound is coming from the powered subwoofer on 1 speaker. What I have done:
- disconnected speaker from amp and reconnected, no change
- changed power connection for sub to a different point, no change
- switched speaker off at switch on back (hum disappears as sub is not powered). Switched the speaker back on and the hum returns
- powered everything off and then back on again after 1hr - hum returns from same speaker
- powered everthing on and waited for 1 hr: hum slowly fades away but when I start playing music from either Tuner or CD the hum begins again before finally fading away and then everything is - for the moment - crystal clear...
Disconcerting. Not sure if this is a defect or somehow normal.
Any guidance would be appreciated as return is not an option.
Edited by Music4Life, 21 April 2012 - 09:16 AM.
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