It may depend on your TV. My Samsung QN65Q70RA seems to allow only one or the other, i.e,, there is a choice in the Settings between audio output to TV speakers, or audio output to BT speakers, but not to both at the same time. There is also a third choice of speaker output. It could got through an optical audio connection, presumably to an AV receiver. But again, I do not see that one can deliver audio to TV speakers and any other choice of audio output at the same time. Possibly there is a way of getting around this but to the best of my knowledge my TV does not allow what you describe to be done.