Can other people hear the TV when the TV Connector is connected?
You have the 3.5 mm audio cable plugged into the AUDIO OUT port of the television. Check the audio settings of the TV to enable the loudspeakers to be used in parallel.
Alternatively, use the optical (TOSLINK) cable instead of the analog 3.5mm audio cable to connect the TV Connector to the audio source.
For more information, see the TV Connector User Guide.