[Firmware Version Unsupported]

Ha! I thought I didn't have an account,but it turns out I had made one a long time ago to get sweet beta firmware downloads. 

Glad it worked! 

[Firmware Version Unsupported]

I have a similar issue, my old flirc is on Firmware: v255.7.0 [0x020A07FF]. The GUI just says it's too new and won't update it.

On ubuntu, the flirc_util is still bundled with the GUI. So what I did was:

sudo chmod +x /usr/bin/flirc_util

then you can run things like

/usr/bin/flirc_util version

That should tell you if it's working. Now to update it here is what I just had to do (what a pain in the balls).

on Ubuntu:

sudo apt-get remove flirc
wget http://apt.flirc.tv/arch/x86_64/backup/flirc_1.2.6-1ubuntu1_amd64.deb
sudo dpkg -i flirc_1.2.6-1ubuntu1_amd64.deb
Flirc

Then it updated the firmware to 2.6.0. Half way there!

sudo apt-get remove flirc
(gets rid of 1.2.6 version)

sudo apt-get install flirc
(re-installs 3.1.0)

Flirc
(now it prompts you to upgrade the firmware)

I don't really enjoy having to scrape through archive.org to find the old repository to get an older version, kind of lame.