Is an Annuncicom 100 with standard firmware able to receive audio using RTP protocol ?

Not with the standard firmware, but by using the Barix Instreamer Standard firmware or with the following ABCL firmwares it can send and/or receive RTP streams :

• Annuncicom Fullduplex application contained in the ABCL firmware kit
• ABCL IP-Intercom firmware
• ABCL STL firmware
• ABCL Any to ALL firmware