Thank you so much for the advice. Was about to post the log, but decided to update the firmware once more and, after a restart or two, the thing is running like a champ again. Wish I'd tried that earlier.
That's a weird issue without the kernel logs it's like we're guessing what's wrong with your unit but if flashing it solves your case then that's fine. Sometimes unsuccessful flashing may cause some issues I always try 2 to 3 times flashing them before deciding if it's a hardware issue.
What firmware did you flash it again the latest one?
Why not try their TF card firmware?