Hi Robert,
I think what you should do is this:
1. Take one of the non-working phones and unplug the line cord from the base of the phone.
2. Take this phone to one of the working phone locations and plug it in using the line cord of the working phones.
3. Take the working phone to the location of the non-working phone and plug it in using the line cord from the non-working phone.
4. Determine if the problem follows the phone, or if the problem is associated with the line cord/Jack/Wiring of the specific location.
I think that the most likely problem will be the found in either the line cord,Jack or Wiring. I have even seen problems in the RJ 21 that connects to the VG248.I have not seen problems like you have described with the VG (we are curently using 10 VG's running 1.3.1 in our IPT setup).
Hope this helps! Let us know how you make out.
Rob
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