Stereo/Sub issues

[JethroJay]

but the sub only works when the stereo is on the radio and the rest of the time it's dead (AUX and CD it's dead) the remote turn on cable is powering the aerial or something like that

Ive not read everything.
But your subs only working when you have the radio on and not when playing cd or anything...
Could it be due to the fact that youve wired the remote wire to the aerial?

I'm using the block that the stereo came with and wired it into the blue wire on the stereo as that's what the guy at Halfords said to do and also quite a few other people said to connect it to the blue cable as well as that's the remote wire, I wired my sub up in the Astra and that was perfectly fine, nothing wrong with it! So this has got me in a pickle!