Hi, Are these speakers shielded?? I've had a good look around on the net and can't find any details on these. Since getting my Philips 32PW9509 telly, I haven't plugged the speakers back into the DVD player. Worried about shielding especially on the centre speaker. Didn't mind on the old telly but don't want to damage the new one. Can I use the Bush set safely? OR (not being an expert) would it make sense to use the sub and rears, but keep the rest through the telly (it's 'virtual' Dolby) or would I never get it to balance the sound sensibly.? The sound from the telly is ok, but lacks the sub, and for some reason, speech can be quiter than expected with music or background noise.