Roll back firmware

Hi there guys, ever since my Kindle Keyboard updated itself to 3.4 this week it's constantly crashed and rebooted. I've tried restarting and then restoring to factory settings but it still won't work and often crashes as soon as it starts up.

I started a thread here:

http://www.mobileread.com/forums/sho...d.php?t=217473

and it was suggested I post in here and ask if anyone can help me roll back the firmware.

Thanks

Gavaltron