If it is a live image, my guess is that it is something to do with squashfs. I found the following note about recent changes to the default squashfs configuration that sound like they might be related to your problem (“high latency” == “not responses immediately”):
Excerpted from OptimizeSquashFS – User Experience:
- Decreasing the installation image size will reduce cost of mirroring and storing Fedora installation images.
- Decreasing the installation image size will reduce the download time.
- Increasing the block size on the current configuration with EXT4 file system, should increase latency while accessing the EXT4 filesystem. The exact impact is to be evaluated.
- The impact of latency will be reduced, if the plain SquashFS option is be choosen.
I’m not sure if the above change was actually made. Following some of the links leads to a confirmation that a different squashfs-related change was made recently:
I don’t know what, if any, impact the above changes might have had on your experience with Fedora Media Writer, but it seems at least feasible that something along those lines might be responcible for the high latency you are seeing.
Also, squashfs has been known to stall out with some kernel configurations:
It is very complicated. Hopefully the above reading might help you to trace down the exact problem.