I ran into a similar problem years ago on a OnyxVS
CID was a expensive add on and I couldn't get it to work , worked fine on a CID box or SLT back and forth and finally Nitsuko agreed they had designed it too close to the spec and it didn't allow for minor variations .
if the signal works with a Meg-lo-mart CID box or SLT and not on the phone switch I have to say its something the manufacturers should be addressing
