EZ-Flash Air firmware issues: a rollback method is now available
The latest EZ-Flash Air update to Firmware 4 / Kernel 1.05 seems to have caused trouble for some owners.
I tested the new firmware recently, and everything worked fine for me. As it turns out, I was simply lucky.
Back on July 31, an EZ-Flash Air owner started a GBAtemp thread after games began freezing regularly on FW4/K1.05. The trouble started within minutes of the update; before that, the cartridge had worked normally.
More complaints followed. Users described freezes, memory errors, graphics glitches, and sound problems. In a separate thread, one owner's Air stopped being recognized by either a GBA or a DS after a game froze.
Not every cartridge appears to be affected.
But what can the unlucky owners do?
The obvious answer would be to reinstall Firmware 3 / Kernel 1.04. Unfortunately, it isn't that simple.
Installing the original Kernel 1.04 rolls back the kernel alone. The firmware stays at version 4, leaving the cartridge in an odd FW4/K1.04 state.
In early September, GBAtemp user GamerMlg investigated why. They found that Firmware 3 is already embedded in the ezairkernel.bin file, but the cartridge checks its current version and refuses to flash older firmware over a newer one.
GamerMlg changed a few bytes in Kernel 1.04 to make the Air flash Firmware 3 over Firmware 4. More importantly, it worked.
Games that had been freezing on their GBA and DS Lite ran normally again after the rollback. The original poster tried the method and confirmed a return to FW3/K1.04. Another user later reported a successful rollback too.
At first, owners had to edit Kernel 1.04 themselves in a hex editor. That step is no longer necessary.
On September 19, community member ViniciusR0 uploaded a ready-made rollback archive. It contains both a modified and an original Kernel 1.04. Install the modified file first to restore Firmware 3, then the original kernel. The final result is FW3/K1.04.
Each file in the archive must be renamed to ezairkernel.bin before its turn on the SD card. The author of the method also recommends backing up the SD card first, then deleting and rewriting the games in NOR after the rollback because FW4 changed how NOR is managed. If the firmware does not change, do not keep reflashing. See GamerMlg's full instructions for the procedure.
And EZ-Flash's response? Owners reported the problem, worked out why a normal rollback fails, made a forced downgrade possible, and prepared a ready-to-use file. EZ-Flash has not replied in that thread so far.
If your Air works fine on FW3/K1.04, I wouldn't rush to update it. If you have already updated and haven't noticed any problems, perhaps you were as lucky as I was.