Actually it sounds like to me is that this person with the Multiplexors
can't log in at all rather than having a throughput problem.

It could be name brand dependent.  Some were downward
configurable to behave like 8, or 4 channel versions.

Then again it could be a wiring issue.  Are all the mux ports on the HP
end wired to modem ports?  Does the mux even require these signals?

This could make it appear that some ports are not working.

It is possible that some of them are wired into modem ports and some are
not, whereas the mux wants these signals.  It is even probable that even
though the mux wants these signals now, that those ports can be
reconfigured as to not want them.  In the old days when this wasn't the
case you could "spoof" modems and mux ports into thinking DTR was always
high by creative wiring at one end of the connector.  I seem to remember a
relationship betweens pins 4,5,6, & 20, on DB-25 connectors, but I'm fuzzy
on the details.

Tracy Johnson
ANSWERS, Manhattan Beach, CA
Minister of Propaganda, Justin Thyme Productions
[log in to unmask]
"Semper Pollus"
 ADC-2239-5531