Even though I don't have this unit I've read many posts concerning the Ref50. Do you have the latest firmware update.
You might find your answer here check:
www.hometheaterspot.com and follow the link to the B&K forum.
Best of luck
Question about my B&K reference 50 "Please help"
Well, I would sure appreciate any help I could get if someone could help me out. I purchased a new B&K reference 50 in May. I am running it with the B&K 200.5. My speakers are B&W nautilus HTM1, 803s(front), 805s (back). It has ran great since purchasing it in May, and has never been tampered with by anyone other than myself. Yet, Yesterday when the wife and I went into the media room.. Nothing would work... The reference 50 is hung on "PLEASE WAIT".. Its nonresponsive to the manual controls, as well as the remote control. I checked it again this morning, and it still says "please wait". I have read the owners manual cover to cover, and couldnt find anything within the manual itsself or the troubleshooting section, that referred to this problem.. any advice would be most appreciated. Thanks in advance.