SNES for CRT TV with antenna....no sound

[Siggi Trust]

Hi everyone, registered only to ask about this, I can't seem to find an answer anywhere.
So I just bought a Super Nintendo console and got an old TV to use with it. I tried connecting it to my Full HD TV but there was terrible latency, so I decided to get the CRT but I did get a picture and sound.

Okay so after searching for channels, I found the SNES but there was no sound, there seems to be some buzzing like the sound is there. This is a Sony Trinitron, I tried fine tuning (using something called AFT or something) but it did very little, the picture changed slightly but no sound.

Given that my HD TV got the sound, the cable is obviously working so I was wondering could it possibly be the input on the TV? Yeah and I got sound the TV, I found a channel somewhere so there's no mute on or anything and the volume bar appears when I adjust the volume.
I'm just really lost here, so please anyone help me. I'm no TV expert so if I'm missing anything let me know
Thanks
Regards