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Select DTMF Types
DTMF (Dual-Tone Multiple Frequency) is the tone you heard
when you press a numeric key or * and # key on conventional
telephone. It’s impossible use certain online services (like
online banking service) without DTMF function.
To use DTMF function, you must select a proper DTMF type.
Three types of DTMF are supported by this phone: Transparent,
RFC2833 relay, and SIP info. Your service provider should tell
you which mode you should use. To change DTMF mode,
please connect to this phone by web browser, and click
‘System’ link on the left. Please select a proper DTMF type at
‘DTMF Type’, according to the instruction given by your service
provider.