PCM-SYNC-SOURCE

PCM sync source sets the S0-bus used as a clock by the Voice Call Manager.
Important: This setting is relevant if you use a bus internally and the second bus is connected externally (e.g. to a connection from the ISDN provider). In this case, you should use the external connection as the clock. With the setting Auto the device selects the bus by itself.
SNMP ID:
2.23.19 
Telnet path:
Setup > Interfaces
Possible values:
Auto
S0-1