FXII with a PRI from Time Warner Cable. TWC claims the customer has three way calling. When were adjust the flash timer we do not phase the channel. We have tried all the different values. The time set is is reflected properly by the use of the TAP button, however there is no change on the channel on the PRI circuit. Are we missing something on the FX or is TWC mistaken on the settings on this circuit?

ty,
Gary