So, the relay contacts are in the attenuator? I really don't want to remove the front panel if I can avoid it. Knobs are prone to breakage when removing them. But at least I'm sure that the relay contacts are the problem. If it continues to be an issue, I will have to open it up. I'm wondering if warming the knobs with a heat gun will allow me to remove them without breaking them. When I had to replace a BNC connector on my first 2465, I broke one Knob during removal. Previous owners probably never used 50ohm DC input enough to keep relay contacts clean.
David
