To switch the default sound path and audio for both playback and mod_say_X, it seems you modify 2 things: <X-PRE-PROCESS cmd="set" data="sound_prefix=$${sounds_dir}/en/us/callie"/> <X-PRE-PROCESS cmd="set" data="default_language=en"/> But I'm trying to test a new english voice (amazon's neural Matthew, digits/ivr/currency available here <https://github.com/avimar/freeswitch-sounds-polly/>) Changing the sounds_prefix worked for the audio files, but not for mod_say_en. I found that if I modified /usr/share/freeswitch/lang/en/en.xml: <language name="en" say-module="en" sound-prefix="*$${sound_prefix}*" tts-engine="cepstral" tts-voice="callie"> ... to not evaluate on startup/original, but the current value, then it worked. <language name="en" say-module="en" sound-prefix="*${sound_prefix}*" tts-engine="cepstral" tts-voice="callie"> But now I'm getting this error anytime I use mod_say_en -- even though it's working. EXECUTE sofia/internal/1000@YYYY say(en NUMBER ITERATED 1000) 2020-05-04 20:19:28.963796 [CRIT] switch_channel.c:1436 Invalid data (${sound_prefix} contains a variable) Is this a mistaken error? Was I supposed to modify this somehow else? Thanks. -Avi Marcus