Picked this up a rather cheaply and seems in goodish shape. Quick hook-up with a head & cartridge from my usual SL 3200 provided only one speaker though - Left. On closer inspection the interior "pin" of the red output appears to blanked, ie it's not metal at all but red plastic, and I've not seen that before. Is it possible this turntable is wired differently somehow ? Mono perhaps ? Or is the headshell wiring different between models ?
I'm not adverse to taking it to bits if it's a loose wire somewhere but I'd like to know otherwise - pls feel free to set me straight if I'm missing something ?

For the record I cleaned the contact points on the lines out and also the spring loaded ones at the end of the arm - pretty sure those are not the problem. Was well grounded also.

Many thanks !
S.