Background Sound Too High

On my 43UWX10B connected to Comcast (Xfinity), some of the movies have very loud background sound (music, etc.) that almost drowns out the dialog. For instance, in a party scene, the band music will be very loud compared to the spoken words. In scenes without background sound there appears to be a sound like traffic noise. This only happens on some channels.

I tried adjusting all the audio settings on both the TV and the cable system. Nothing seems to help.

Any suggestions will be appreciated. Thank you.