Hi all I have recently bought a second hand PB-10 from another forum member. The sub has not been working. Incidentally the forum member from whom I bought it has been great and very cooperative with the problem. I have no doubt that he will help to get the problem resolved either through refund or repair, but that will take a few days and in the meantime I have some spare time so I wondered if one of you kind people may be able to help. The sub powers up fine according to its on-light, but upon connection to my Onkyo 905 there is little to no output from the sub. At normal gain levels, i.e. 40% to 50% on the dial, there is absolutely no output from the sub at all. I am using my receiver's test tones on the LFE channel, and all of the other speakers test fine. There is also no pop or grounding hum when the phono cable is inserted. In my experience from other subs it would usually start making a humming sound when the cable was touched against the low-level socket, is this right? Anyway, it's silent. If I turn the gain up to 100% then I can hear the test tones but they are so faint as to be nigh-on inaudible. This surely proves that the sub is connected up correctly? I have also gone through the Onkyo's settings many times to ensure that I have not missed anything. Sub is set to active, LFE to 120hz and I have even tried turning the sub level up from -4.0db to the highest it will go, which makes a tiny bit of difference but not much. I have gone through everything so many times that I am sure I have not made a setup error. I have also tried a friend's Panasonic AVR (cheapo in-a-box type thing) with the same result. Today, I have connected up an iPod via a single phono cable direct to the sub. Same result; at normal gain levels it's inaudible, but at 100% gain it becomes very slightly audible. I have spoken to the original dealer in Kent who have said that they are not familiar with this problem. They were unsure as to whether it would be the driver at fault, the amp plate, connections, etc. They did mention that it would be okay for me to open the sub up to check the connections. They are going to check stock to see if they have any spare amps around for warranty purposes. If not, it will be a couple of months while they order one from the States. However, the amp itself uses strange scrwes with square holes that I cannot open. I could take the driver off as it uses normal Philips screws, anybody know what I should be looking out for? Anybody have experience with similar problems, or does anybody suspect what the problem may be from their experience? Thanking you muchly in anticipation.