The good news: The Efika system runs more stable with the improved system I have been shipped, guess its the one Genesi was using on its fair last month.

The bad news: Still I experience occasional freezes though rare. One main problem still is the log-in screen (dodged by the fair's configuration) where some times the password field does not allow to type into, or other funny variants.

The good news in the bad news: After these freezes I can boot from the installer SD into a terminal and repair the internal sda. Mostly there are a lot of inode problems to be fixed.

The bad news in the bad news: This procedure does not work well. The terminal process can stall entirely or resurrect after a long time (30min!) bringing up timeout messages like:

ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen

:idea: wasn't the intention behind Ubuntu to run without forcing the user to deal with this under the hood code? :roll:

Hi folks, 99 views so far and no reply?

Well my case turned worse: on boot I was greeted by this terminal which always comes when no bootable system is found. /dev/sda2 went missing.

So I installed a new system. But this system freezes regularly with greetings like 'broken pipe', 'deleted inode referenced' or on suspend: kernel panic, not saving, fatal exception in interrupt.

IMHO another internal 16GB flash disk defect, which causes plenty of read/write errors or corrupted directories.

When trying to check /dev/sd* externally terminal stalls.

IMO you aren't getting any replies because no one has anything to add; it seems you figured it out yourself already: the disk is broken. That's what I think is the case at least.
I've always experienced those "atax.00: exception Emask [...]"-type messages with a broken disk or a disk that was dying, so I agree with your diagnosis.