In newer versions of Asterisk it seems to default to /usr/share/asterisk/sounds even with no specific setting in /etc/asterisk/asterisk.conf even though the normal default even in Asterisk documentation for Version 20 says /var/lib/asterisk/sounds
[Nov 3 23:46:02] WARNING[2197][C-00000016]: file.c:824 ast_openstream_full: File for-tech-support does not exist in any format
The file does exist in /var/lib/asterisk/sounds
cp -a /var/lib/asterisk/sounds/* /usr/share/asterisk/sounds/
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