Sat radio crackling and hissing from 1 speaker

[X5rolls]

Regular radio & cd sounds as good as new.

When I switch to XM radio, I get reception but one speaker (dash on drivers side) crackles and hisses so it's hard to hear the broadcast. I still leave it on and listen but not normal. Using other XM stations changes nothing.

Possible the Sat antenna wire or antenna are on the fritz?

XM radio integrated in stock unit, antenna is roundish disc style that fits in palm of hand size, attached to thin wire up from rear hatch door and mounted to roof about a foot in center from rear hatch?

I suspect wire and or antenna is bad, if so, can a shark fin antenna be adapted for XM use? It would look cool compared to small flattish disc.

Thanks in advance.