stream_file first file doesn't play

[Darren]

stream_file() isn't playing the first file.

This example plays nothing:
$agi->stream_file('filename','1');

This example plays filename once:
$agi->stream_file('filename','1');
$agi->stream_file('filename','1');

Here is the AGI debug log:
AGI Rx << STREAM FILE filename '1' 0
-- Playing 'filename' (escape_digits=1) (sample_offset 0)
AGI Rx << STREAM FILE filename '1' 0
-- Playing 'filename' (escape_digits=1) (sample_offset 0)
AGI Tx >> 200 result=0 endpos=8781

It looks like it tries to play the first file, but there is no AGI Tx following it (like there is every other file it plays).

I found this post, but it didn't resolve my issue.

I'm using: PHP Version 5.3.28 and phpagi 2.20