The outputs of the BB are not ‘balanced’ (I don’t believe), thus TS type cables are appropriate. Not sure if using TRS cables would be a possible cause for any noise from the BB, but if your mixer has ‘balanced’ 1/4" inputs that you are using, it’s possible the ‘ring’ connection of the TRS plug in the BB has no connection which the mixer may not like as the ‘ring’ is used as one side of the signal connection into the mixer.
Would it be possible to post a short mp3 snippet of the noise you’re hearing?