Thanks for the timely response.

I have found some used replacement phones.

The problem with the old phones was a drop in the audio. Basically they would just go dead in the middle of a conversion.

I have disassembled them, cleaned all contacts and put them back together --to no avail.

What would cause this problem? What part(s) needs to be replaced? And what does refurbishing really change in the old phones?

Again thanks for your interest. --Glen