Hi, I am playing a file to a landline number. the format of the file is as follows: [root@static-host var]# file message.wav message.wav: RIFF (little-endian) data, WAVE audio, ITU G.711 mu-law, mono 8000 Hz In my vars.xml file I have used the following codec prefs: <X-PRE-PROCESS cmd="set" data="global_codec_prefs=PCMU,PCMA,GSM"/> <X-PRE-PROCESS cmd="set" data="outbound_codec_prefs=PCMU,G722,GSM"/> However, when freeswitch plays it, it always chooses the L16@8000hz codec. I'm not understanding why this is so. EXECUTE sofia/external/5135692990@208.78.161.197 playback(/var/message.wav) 2009-12-22 17:16:57.357048 [DEBUG] switch_ivr_play_say.c:1135 Codec Activated L16@8000hz 1 channels 20ms 2009-12-22 17:17:30.777182 [DEBUG] switch_ivr_play_say.c:1429 done playing file My basic intent is to avoid on-the-fly transcoding, while having a high quality audio playing on PSTN. Have I configured it wrong or does this transcoding always happen? Thanks, Vinuth.