I can see that sometimes my server product some logs like: deb9157a-b9b1-11e3-8ee1-7b004e0e7c32 2014-04-02 00:03:44.083032 [ERR] switch_rtp.c:749 No audio stun for a long time! 8c9f55cc-b9b8-11e3-9cca-7b004e0e7c32 2014-04-02 00:21:02.441130 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:32:04.021509 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:32:35.021902 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:33:05.061286 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:33:36.061678 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:34:06.101062 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:34:37.101453 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:35:07.121681 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:35:37.161065 [ERR] switch_rtp.c:749 No audio stun for a long time! a7801e9c-b9ba-11e3-9f47-7b004e0e7c32 2014-04-02 00:36:08.161457 [ERR] switch_rtp.c:749 No audio stun for a long time! 74c1f71e-b9fb-11e3-bbbd-7b004e0e7c32 2014-04-02 08:14:35.502605 [ERR] switch_rtp.c:749 No audio stun for a long time! c323e07a-b9fb-11e3-bc46-7b004e0e7c32 2014-04-02 08:15:02.921673 [ERR] switch_rtp.c:749 No audio stun for a long time! fa17e09a-b9fb-11e3-bd18-7b004e0e7c32 2014-04-02 08:16:35.121138 [ERR] switch_rtp.c:749 No audio stun for a long time! fa17e09a-b9fb-11e3-bd18-7b004e0e7c32 2014-04-02 08:17:06.121531 [ERR] switch_rtp.c:749 No audio stun for a long time! 43945544-ba03-11e3-8df9-7b004e0e7c32 2014-04-02 09:09:08.621875 [ERR] switch_rtp.c:749 No audio stun for a long time! 05e67bae-ba09-11e3-a24c-7b004e0e7c32 2014-04-02 09:50:28.321208 [ERR] switch_rtp.c:749 No audio stun for a long time! b151ab62-ba09-11e3-a4da-7b004e0e7c32 2014-04-02 09:58:45.491465 [ERR] switch_rtp.c:749 No audio stun for a long time! 552384de-ba0c-11e3-afc5-7b004e0e7c32 2014-04-02 10:14:03.691235 [ERR] switch_rtp.c:749 No audio stun for a long time! 04bc9112-ba0b-11e3-aabc-7b004e0e7c32 2014-04-02 10:16:39.392036 [ERR] switch_rtp.c:749 No audio stun for a long time! 04bc9112-ba0b-11e3-aabc-7b004e0e7c32 2014-04-02 10:17:37.411787 [ERR] switch_rtp.c:749 No audio stun for a long time! 04bc9112-ba0b-11e3-aabc-7b004e0e7c32 2014-04-02 10:18:07.431169 [ERR] switch_rtp.c:749 No audio stun for a long time! 2e316a40-ba10-11e3-8076-7b004e0e7c32 2014-04-02 10:41:28.251996 [ERR] switch_rtp.c:749 No audio stun for a long time! 7396150e-ba10-11e3-8186-7b004e0e7c32 2014-04-02 10:43:24.291472 [ERR] switch_rtp.c:749 No audio stun for a long time! 388ba6ac-ba12-11e3-8801-7b004e0e7c32 2014-04-02 10:56:48.411568 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:10:06.051664 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:10:36.091046 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:11:06.111419 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:11:37.111820 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:12:07.151202 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:12:38.151594 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:13:08.190977 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:13:39.191370 [ERR] switch_rtp.c:749 No audio stun for a long time! 5c7c26d8-ba10-11e3-8125-7b004e0e7c32 2014-04-02 11:14:10.191752 [ERR] switch_rtp.c:749 No audio stun for a long time! abb38326-ba16-11e3-9cb0-7b004e0e7c32 2014-04-02 11:27:40.391902 [ERR] switch_rtp.c:749 No audio stun for a long time! 75cee1e2-ba1b-11e3-b14f-7b004e0e7c32 2014-04-02 12:01:57.731915 [ERR] switch_rtp.c:749 No audio stun for a long time! My server is not behind firewall or router, I want know why the freeswitch still product these logs? Is something wong with my config?