Onkyo HT-S3405b. Amplifier hum?

[Kaj]

Hi guys,

i hope you can help, i recently purchased the Onkyo HT-S3405b system from best buy. in the last few days i have noticed a slight hum coming from the sub and wanted to know if this is normal or if there is anything that i can do about it?

Any help would be much appreciated i have tried turning off all electricals around it but no luck

 

[arbk66]

Mine came from BB as well and I'm not aware of any hum, had a closer listen around it a few minutes ago but no unwanted noises to be heard.

The sub sits on its own against a wall about 3 feet away from the nearest electrical device.