General :: Audio From Tablet To Phone Through Bluetooth?

I've got a conundrum that I can't seem to work out from Googling. I suppose I will give the background then my question.

I use my xperia z2 tablet at the gym to watch TV shows because the treadmill is even more uninteresting than the landscape around my place. I don't like to be hooked up to it via headphones because I don't want to accidentally pull it over. So - I use a bluetooth audio receiver I plug my headphones into, and they receive the audio from the tablet (which is paired with the receiver).

I would prefer to just use my phone in place of the receiver, because the receiver is cheap and doesn't work so well (and i cant believe it can't be done).

I thought two options could be:

1 using the phone as a bluetooth receiver, or
2 somehow using the wifi hotspot on the phone to enable the audio from the tablet to play through the phone.

Does something already exist or is it even possible?