Hi, I have a uc500 my problem is:The 4 ports FXS is dead, I don't have a tone signal, ring tone, etc.I review the status of port 0/0/0:show voice port 0/0/0Foreign Exchange Station 0/0/0 Slot is 0, Sub-unit is 0, Port is 0 Type of VoicePort is FXS V...