Facts don't lie, and my only argument is as I stated above: phone systems aren't audio gear. Phone lines should be balanced 600 ohms and if the designer made the page port the same as a station port then you may or may not need a balun, depending on how he did it. I think your tests prove that with that particular system the WMT1 is needed, but there are others that won't. Read the manual and see what it says. In this case there is definitely something about the connection to the amp that the page port doesn't like. Should you always use a WMT1? If you know what you are doing and can understand what's going on like Ralph does I certainly would carry one in my truck. Try it without first and if that's no good see if the WMT1 makes it better. But either way make sure you know how to connect to the amplifier first so that an improper connection or input isn't really to blame.

-Hal

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