My brother says he is occasionally getting a shock when using his wired
> phone (ATT Trimline) with DSL filter on a SBC POTS/DSL line. Is the > phone shorted?
Almost anything is "possible".
Getting a shock from a _plastic_ telephone housing is *VERY**UNLIKELY*, however.
Ring voltage on U.S. telephones is circa 90VAC. This is enough to give a non-trivial shock. *IF* there is a path for it to 'escape' through, that goes through the person holding the phone.
[TELECOM Digest Editor's Note: If a person's hands are wet (or, for example, a person is in a bathtub) having a phone with you is _very dangerous_. Water is a very good conductor of electricity. PAT]