Sandisk Sansa Clip + SD card not working in both firmwares, but differently

[tsl]

Hello, I have this kind of problem.
It started yesterday when, on my way home from work, I realized I left my clip+ playing, so I shut it down in my pocket without looking (but I heard headphones stop playing). Today I tried to turn it on, and found out it was frozen (I don't know whether it froze just as I turned it off, but it looks likely).

After few resets, sdcard removing and reinserting, it booted fine with and without card into Rockbox, but in OF it just froze in an instant. I even bought a new card (in computer it shows fine, it's 8GB Class 4 AData card, and it's not fake... old card was some very old, scratched, unbranded 8GB Class 10 card, but it worked until now)

I also tried updating both OF and Rockbox, reformatting internal memory and sdcard (just the new one, but as the symptoms are all the same, I believe it is not a card problem), installed dev version of Rockbox (then reverted back to stable).

Now it does this:
Booting OF WITH sdcard inserted - boots, shows animation, says refreshing (empty card, empty internal except of the rockbox stuff), then shows Language dialog or standard menu (defaulting on Settings) and doesn't respond. Strangely enough, if I pop the card out, it almost instantly unfreezes.

Booting OF WITHOUT sdcard inserted - everything works as expected (except I don't have enough space for my songs). When I insert the card now, the same freeze appears, and if I pop the card out, it unfreezes like nothing happened. I guess it shouldn't work that way though.

Booting the Rockbox WITH sdcard OR plugging sdcard in after boot - boots without problems, but sdcard is not shown in files, System info shows MSD: Not present and it is not listed under Debug - Disk info (but should it? I'm not sure). The player normally plays (at least before the format it did)

As I was roaming the forums and clicked through the Debug menu (keep out, I know), I realized that Partitions show all four as S:0 T:0 0MB... it doesn't look good, does it? Maybe that's whole root of problem, when I froze, it forgot the partition table... but why is it even booting in first place? It's a mystery to me.

Thanks for your time... and sorry for the long post, I didn't know how not to forget some relevant info. If I did though, please tell me what to check and post.

[tsl]

Also, if I plug the sd card in when booted in Rockbox and connected to PC, it reports this 8GB card as 30,6MB unformatted, which can not be formatted. Does rockbox at least have some system log? It might help.