Report "Hi, just bought a pair of second hand (but look as new) Fostex PM2 MK2 active monitors. the problem is there is a hissing noise coming from them, with or without an audio cable connected. rang SCV London (Fostex Distribution), they said it could be the electricity supply if both speakers are exactly the same. So i took the speakers to my Mum's house and they are the same there. Could somebody tell me what is likely to be wrong with them, please. thanks Simon"