hi i've recently bought an old'ish set of kenwood separates but for some reason one of the channels (the left i think) doesnt work properly, only the tweeter seems to be working or if the sub is working its very quiet! has anyone got any ideas how i can fix this or if they have had a similar problem!? i cant afford to go buy a new amp and even if i could i really like these separates! lol! thanks in advance... mikee