mod_mp4 module is looking for Hint tracks in the .mp4 file. "Hint tracks are a series of instructions in a mp4 container file that tell a server how to transmit packets." To create hint tracks for a mp4 file is fairly simple with the mp4creator program, we just executed the: mp4creator -hint=<track to hint track number> [-p <payload>] <mp4file> As we know .mp4 has both video+audio data in it. We could also find audio and video encoding information of a .mp4 file as shown below. #mp4info minnale.mp4 mp4info version 1.5.0.1 minnale.mp4: Track Type Info 1 video MPEG-4 Simple @ L1, 97.833 secs, 136 kbps, 176x144 @ 12.000041 fps 2 audio MPEG-4 AAC LC, 97.568 secs, 64 kbps, 32000 Hz 3 hint Payload MP4V-ES for track 1 4 hint Payload mpeg4-generic for track 2 Metadata Tool: mp4creator 1.6 Now we are getting "Invalid codec mpeg4-generic!" error. Please guide me. Do we need to have mpeg4-generic codec in Freeswitch server? Thanks & Regards, Muqtheear.S