RTMP streaming fails frequently on Box

I have written an application that is attempting to play RTMP streams. These have a standard RTMP URL as well as an additional PlayPath being set using .SetProperty("PlayPath",...)

The result in playing these back is somewhat random. Sometimes they will play fine, other times however the file will not begin playing and will instead only start when the app is exited or another file is played.
In the cases where it does not play, the DEBUG log shows that it is receiving packets, just not displaying anything.

The problem seems to occur most on the 2nd or 3rd playback attempt.

To reproduce:
Add repository http://noisymime.org/boxee
Install the SBS app
Attempt to play a file, if it is successful, halt the playback and try the next file in the list.

The RTMP URLs in the app are all correct, I have verified that ones that do not play are correct and will download OK in things such as RTMPDUMP.