... 96ms, Hand free Speaker Phone Support Voice Gain Setting, VAD, CNG DTMF:Support SIP info, DTMF Relay, RFC2833 ... to SIP1 and SIP2 server at the same time SIP application: support Call forward/ transfer/ holding/ waiting ... pickup/join call/click to dial/call park SIP support SIP domain, SIP authentication (none, basic, MD5), Peer to ... or configuration file) Support Syslog voip phone sip phone ACOM IP ...