I have a UC540 with an analogue PSTN line with caller ID activated on that line. When I use a standard fixed telephone on the above PSTN line, I can see the number of the person who is calling me (Caller ID). When I connect the same analogue PSTN line on my UC540, I always get 'anonimous'. I can't see the caller's number. How can I fix this because the caller ID is important to me. On internet, I read that there are two protocols (DTMF and FSK) for caller ID on PSTN lines, but I can't find which protocol the Cisco UC540 is using. I have looked into the settings of the FXO ports on the Cisco UC540, but I can't find any information. Can anybody help me? PS: I'm from Belgium (Europe).
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