This is fairly reproducable. It is occuring with a specific image (but not always goes into an infinite loop). URL for the image is here:

http://cf2.imgobject.com/t/p/original/3FdJh9N2nLLSmxyhcuuApeRm2Ot.jpg

When this happens, there is usually lots of image decoding going on (multiple JPEG photos are decoded at once, in several threads), so it is possible it might be a threading problem related to the decoding.

Here's a stacktrace where the image decoding got stuck (consuming 100% of a CPU core):

"pool-3-thread-14" prio=6 tid=0x05619800 nid=0x2fc8 runnable [0x0fb4f000]
   java.lang.Thread.State: RUNNABLE
at com.sun.javafx.iio.jpeg.JPEGImageLoader.decompressIndirect(Native Method)
at com.sun.javafx.iio.jpeg.JPEGImageLoader.load(JPEGImageLoader.java:223)
at com.sun.javafx.iio.ImageStorage.loadAll(ImageStorage.java:294)
at com.sun.javafx.iio.ImageStorage.loadAll(ImageStorage.java:244)
at com.sun.javafx.tk.quantum.PrismImageLoader2.loadAll(PrismImageLoader2.java:107)
at com.sun.javafx.tk.quantum.PrismImageLoader2.<init>(PrismImageLoader2.java:41)
at com.sun.javafx.tk.quantum.QuantumToolkit.loadImage(QuantumToolkit.java:607)
at javafx.scene.image.Image.loadImage(Image.java:942)
at javafx.scene.image.Image.initialize(Image.java:722)
at javafx.scene.image.Image.<init>(Image.java:625)
at hs.mediasystem.util.ImageCache.loadImage(ImageCache.java:27)
at hs.mediasystem.beans.AsyncImageProperty$2.run(AsyncImageProperty.java:58)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)

My part of the code at ImageCache looks simply like this:

      byte[] data = handle.getImageData();

      if(data != null) {
        image = new Image(new ByteArrayInputStream(data), w, h, keepAspect, true); // <-- infinite loop here

        CACHE.put(key, new ImageSoftReference(key, image, REFERENCE_QUEUE));
      }

There's very little I can do to prevent this as the data is coming from external sources, and the end result I need to restart my program -- the image decoder should definitely never go into any kind of infinite loop. However since the image often decodes just fine, this leads me to think that there is more going on than simply "bad" input data (and so it may not even be specific to this image).

I hope this helps to track down the problem, if you need more information or more tests, please contact me. If you give me some detailed instructions I may be able to pin-point the location of the loop more closely with specialized tools.

EDIT:
I added a synchronized block around the new Image() constructor, like this:

        synchronized(ImageCache.class) {
          image = new Image(new ByteArrayInputStream(data), w, h, keepAspect, true);
        }

That did not make any difference. It is the only location in my program where Image objects are constructed.