CAL Supermash module

Hi, my first post so I hope I can get some feedback.

I run a CAL System 1 DAC with an INDUS 20 bit 8x module which I think sounds great. I recently acquired a SuperMash 1 Bit module. When plugged into the MASH module port of the DAC it does send through a signal but it is seriously distorted and unlistenable (overlayed with white noise).

I found a Stereophile review of the DAC which provides a description of the SuperMash module:

http://www.wghwoodworking.com/cal/CAL_System_1.pdf

On p137 of the review, second paragraph, it says "To use the SuperMash module, a small, auxiliary circuit board must be properly inserted." I can't see anywhere in my DAC where such an auxillary circuit board would go and one wasn't provided with the module.

I have a MASH IV module which died some time ago and the SuperMash came as a package with another INDUS which is also "dead" so it seems these modules can be temperamental.

I was hoping someone may have experience with this set up and specifically with a SuperMash module and can help with advice if indeed there is a need for an auxiliary board for it to work.

Has anyone successfully repaired one of these modules, hey are encased in some sort of composite material and resemble a brick, which would require breaking into.

Any help would be appreciated.