Roth sound bar sub - buzzy

[Tiggsy]

My parents got a new TV and Roth sound bar to boost the sound without the faff off full surround. Its a superb bit of kit for under £200 BUT - the sub "buzzes" with low/loud noise (batman film, for example). I swapped the sub (at Richer Sounds) thinking it was a fault - but it does the same thing. The sub volume isnt even set very high....just enough to add some "umph" to the sound track.

Typical of cheap sub or should I replace with a different model? (all the reviews I read for the bar were very good. I sounds just like the speaker is vibrating so much it "buzzs" - almost like a loose screw is inside it! (but two separate units do the same thing!)

[VEX]

Does it buzz with nothing connected, or only when the sound bar is wired it?

Is it on the same mains socket?

V.

[nogsk]

I have the Roth bar1 and no buzzing from the sub, could be a connection, range or interference issue?

[Tiggsy]

sorry - bad description - the buzz is the unit vibrating with low base tones (like in the opening of the dark night) - its as though a component in the sub speaker is shaking with the "booming" tones and vibrating along. SO in an action scene....where my (proper!) sub at home makes the sofa shake with occasional deep noises.....my mums makes a buzz! My first thought was a loose "bit" inside, but both do it!