It's the only thing I can think that would break both playback and upload. The file ends up nicely in my recording folder:
# locate 1d6f8
/var/lib/freeswitch/recordings/pbx.example.com/1d6f8e21-3038-4334-9302-81ed165ef213.mp3
# file /var/lib/freeswitch/recordings/pbx.example.com/1d6f8e21-3038-4334-9302-81ed165ef213.mp3
/var/lib/freeswitch/recordings/pbx.example.com/1d6f8e21-3038-4334-9302-81ed165ef213.mp3: MPEG ADTS, layer III, v2.5, 32 kbps, 8 kHz, Stereo
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