You mean the two long screws on both sides of the RS232 connector (that screw the cable in)?

No, I didn't. Didn't think it would make a difference but I'll try.

Thanks.

800v4, 861v8, HD621, PS3 slim, analogue speakers, Anthem P2 Amplifier (2 Channel), Proceed BPA-3 Amplifier (3 Channel), 2x HSU VTF-15 Mk2 subs, 2x HSU VTF-3 Mk5 subs, 2x PSA XS30 subs.