What is your offhook voltage? 5-8 VDC, OK. More, or less, bad news. Also, the P-sonic systems I have installed like that system have the capability of operating with a lower on-hook voltage, i.e. 30VDC rather than 48VDC. Check on-hook voltage and whether or not the 'mother station' is adjustable/progammable for different on-hook voltages. The systems do strange things with working lines that are not supposed to be working. Found out the hardway that some p-sonic systems were shipped with only line 1 'turned on'. I have used 1 of their older systems for several years with no problems at all.

When I was young, I was Liberal. As I aged and wised up, I became Conservative. Now that I'm old, I have settled on Curmudgeon.