There is no mod_av in the build modules.conf. The mod_h26x is build and loaded, but the vp8 codec have an own module (mod_vp8). I'm not sure I understand you correctly!? The problem is, that the "VP8" is not a correct setting for "global_codec_prefs" and for "outbound_codec_prefs". Von: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] Im Auftrag von Stephen Dame Gesendet: Montag, 10. August 2015 13:44 An: 'FreeSWITCH Users Help' <freeswitch-users@lists.freeswitch.org> Betreff: Re: [Freeswitch-users] Error msg "Invalid codec VP8! Is mod_av compiled and loaded? Also to use the h26x codecs in mod_av you need to diable the passthru codecs Regards, Stephen From: freeswitch-users-bounces@lists.freeswitch.org<mailto:freeswitch-users-bounces@lists.freeswitch.org> [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Alexander Haugg Sent: Monday, August 10, 2015 7:34 AM To: freeswitch-users@lists.freeswitch.org<mailto:freeswitch-users@lists.freeswitch.org> Subject: [Freeswitch-users] Error msg "Invalid codec VP8! Hi All, I'm using the actual freeswitch on Ubuntu in version 1.7.0+git~20150807... I added the VP8 codec in the vars.xml for global_codec_prefs and for outbound_codec_prefs. WS on Port 5066 is enabled and I use the "sipml5 demo client" as client. Normal audio calls works successfully (opus) but I get the error message in the CLI " [ERR] switch_core_codec.c:665 Invalid codec VP8! [ERR] switch_core_media.c:2671 Can't load codec? Mod_vp8 is build and in the modules.conf.xml enabled What can I do that the freeswitch allow the VP8 Codec with SIP? Thanks a lot!