Doepfer

Hi, I've just bought a new A-109 which doesn't produce any sound out
of the left channel of the panning unit. There doesn't look like
there's any break in the connection to the socket itself, though there
is a jumper (J9) that isn't connected. Should it be? If so I'll have a
hunt round for a jumper; presumably if it shouldn't then the unit is
defective and will need to be returned?