No audio on TV while casting/ mirroring from phone.

I'm wondering if someone can assist please?

I join a meeting on my phone.  I go to google home and start mirroring to my new smart kogan brand tv. I have the picture on the tv but not the sound.  The sound plays on my phone.  

I can't see any settings to change on the tv, could it be the zoom app?

This only happens on my new kogan tv. (Not on samsung phone to samsung tv)

Thanks in advance.