I have a problem with my Cambridge Audio Azur 540A. I've had it nearly 4 years now and for the past year or so it has this annoying issue where, when I switch it on, the speakers have a loud pop and then it cuts off and the protection light flashes. It also happens when I have my headphones plugged in. It appears to be random, and can happen multiple times in a row until eventually it will work as normal. Does anyone know what the problem is? Is it the amp its self? I am running 2 B&W 685 from it, no sub. On a side note, I feel like I want to spend some money. I'm thinking a new amp now, and later some speakers. I have a £400 to £600 budget on an amp, with a view to spend £800 on some speakers in the future. I am aiming for a cinema setup, so would I benefit from perhaps a pair of 683s, and have the 685s at the back of the room? I also have a BK Monolith (I know) which I am not using at the moment because I am in a small room. I am moving to a new house soon with a larger room 12m by 19m and I am not sure the 685s will cut it. Any advice is much appreciated!