Jvc sucks

I bought a jvc led tv.i need to connect it to my sony 6.2 home theater.the only audio output on the tv is a headphone jack(3.5mm jack).when connected the sound comes through but there is a high pitched noise coming from the sony system.i have tried isolators,extentions adapters and no luck.i tried to contact jvc sa n their website claims to be hacked.what **** service is this?i honestly should have stuck to Sony