Sound bar problem

My JVC/Roku TV has terrible speakers so I bought a small sound bar. The SB can be connected via Bluetooth, which my TV doesn't have. One can also mate the two with an optical cable, but I couldn't get any more than a pulsing sound that way, no matter what settings I changed in the TV audio settings. My last resort was with a 3.5mm auxiliary cable, but the only jack in my TV was for headphones and using that greatly limited volume... since TV manufacturer don't think the average person is savvy enough to not blow their eardrums out if left to their own devices. RATS!! So what I did was open the back, cut the factory speaker wires and spliced them to a 3.5mm aux cable and plugged that into the sound bar. Worked like a charm, except it has a constant low volume static similar to what a poor connection would sound like... but the static doesn't change if I fidget with the plug. Also, and this is not consequential to my audio enjoyment but it might help in noodling this problem out; when the TV is off but the sound bar is still powered up, the sound bar buzzes just like when it's first plugged in and you pass the signal tip & ring past the ground contact, but not as loud. Do I have a grounding problem or did I miss something obvious because I'm not up to speed on all thing audio like the experts here?