[Icecast] Delay playing some streams on Android

[M M]

I'm writing an Android app to play streams.  I use the standard Android "MediaPlayer" library to play streams.  I've noticed that some streams start playing without much delay (MPR), but others take quite a while to start (WFMU).  The only thing changing in my code is the URI of the Icecast mountpoint.  My test device is a Nexus 5 running Android 5.1.1.

http://current.stream.publicradio.org/kcmp.mp3 starts playing in about 2 seconds.  It's a 128 kbps stream from Minnesota Public Radio.

http://stream0.wfmu.org/freeform-128k starts playing in about 9 seconds.  It's a 128 kbps stream from WFMU.

The problem gets worse as the bitrate goes down.  32 kbps streams take quite a while to start.

I don't notice this problem in iOS code I've written.  I also don't notice it in VLC.

You can view the headers with:

curl -s -D - http://current.stream.publicradio.org/kcmp.mp3 -o /dev/null

StackOverflow has several posts about this.  For example: http://stackoverflow.com/questions/6582908/why-does-it-take-so-long-for-androids-mediaplayer-to-prepare-some-live-streams.

Any idea what's going on?