PSW 303 Hum

Just bought a new surround system:
Polk RM 20
Polk PSW 303 sub
Onkyo TX-SR674

I'm expierencing a hum on some of the different surround settings. I purchased the ground loop isolator, suggested in the manual, but it doesn't seem to do anything. Any other suggestions -- I'm guessing this is not that uncommon, there must be a better solution.
Post edited by mvsainsbury on

Comments

  • zingo
    zingo Posts: 11,258
    edited March 2007
    Check for loose connections or redundant connections (if you happened to wire two things into the same input). That is where I would start.
  • Serendipity
    Serendipity Posts: 6,975
    edited March 2007
    Check if "Double Bass" or something like that in your Onkyo's settings is set to "on". It bridges the front's low frequency portion + all other speakers set to small + the LFE to the sub. Sometimes the front channels fed to the sub on my Onkyo cause the sub to hum.

    This setting creates a redundant connection, i.e. it is like connecting both speaker-level and line-level inputs to the sub.
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