6500 stays idle, source exhaust pump indicates off, the instrument couldn't turn on tuning, red light on control board near "sample flow" mark, green light near "gas 2" mark keep flashing when ion source gas 1 line is blocked from the but stay solid green when it is open, click sound from the back can be heard when the ion source is attaching on. There is not obvious liquid in the block. When the line from source exhaust is taken off from the venturi block there is not gas flow. What is at fault here? Thank you,