I was wondering if anyone has implemented an external volume control for modern Stern machines? Marco sells one 502-6953-55 (see image below) which is intended for SAM and SPIKE1 and it explicitely says it will NOT work with Spike2 machines. Seems odd to me, but before I start digging into wiring and schematics, I was wondering if anyone has crossed this bridge already.
spike1 (resized).jpg