Hi, I'm new to this group and was wondering if someone could give me some advice on the pro-logic system in my '89 C70. The problem is that when i'm playing music at any volume, the sound is great out of the normal speakers but goes extremly quiet at certain points of the cd, as though the centre speaker isn't being amplified or is 'blown'. I have pulled the control knob fully out and turned it to max and it makes no difference. It appears to be the same on pro-logic and 3ch. If I play a cd without either, there can be gaps in the music, where i assume it is mean't to be playing through the centre speaker. As you can imagine, this is very irritating, and ruins what would be an amazing sound system. Does anyone know if there is an easy way of testing the speaker and if it is easy to replace, as i don't want to force the plastic covering and break/scratch anything!!!! If all else fails, how can i disable the centre speaker? TIA Philcol