Hello

I am having a problem with a pair of beolab 6000 connected to the auxiliary output on a Sony smart TV through a aux-phono cable which is then connect through direct line input on the beolab 6000. 
there is a constant humming sound coming from the speakers increasing with the volume and constant when volume is muted. I have read in other threads several different reasons for this problem and I have tried connecting speaker to same outlet as tv- this doesn’t work.

I have read something about pre amp in the tv? And making a earth loop? And I was wondering if anyone could help me.

thanks in advance.