Hadn't considered the faux aluminum angle:) The cable would be a cheap fix. I'd like to hear someone try it.
We go down thi road any further and this will win up in the DIY section;)
yes you are right my bad
you could try a 3.5mm audio ground loop isolator/noise eliminator cable ( 2 small audio transformers inline for those that don't know ) Think their range is 20-20k and they have a 3db boost if I recall correctly. Mine does anyhow
In addition to stopping the giant free antenna/ground problem it would eliminate any dc offset ( and control the driver better ), as well as any digitalgenic RFI that intermodulates with audio frequency.
You might lose some of the high highs.
They are fairly cheap.
You'd at least know if the culprit was the cable at that point, or something else ( like fake aluminum )
Just throwing out another idea it may not be worth it for you.