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- Incorrect settings used for the OBI110 extension in NocTel
- Forgot to create a NocTel extension for the OBI110VoIP server configuration in NocTel for the OBI110 changed without updating the SIP user and password credentials on the OBI110 as well
- Improper settings for LineInUseVoltageThreshold and/or LineInUseCurrentThreshold
- Intercom/paging system cable connected to the Phone port when it should be in the Line port
- Incorrect cable for the intercom/paging system is connected to the OBI110's Line port
- OBI110's ethernet port is connected to a switch that does not have the port configured for voice VLAN (or whatever configuration is used for NocTel handsets)
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