If you add an error listener to a com.sun.media.jfxmedia.MediaPlayer, even if immediately after creating the player, the listener may miss important error conditions. This may happen, for example, if the format is determined to not be supported too quickly before the error listener can be added. The issue is the client will never know about the condition and the player will not give any further indication of the failure. A quick fix for this is to cache error events until a listener is registered then dispatch them to the first listener registered so the client can be notified properly. This particular bug is causing spurious failures in the test harness which requires re-running the tests manually to ensure the section being tested is working properly.