Hydra SD Card reading problem

Hi all.

I have a problem to read all files from SD cards (only one work). I have tested it on two hardware sets.
There is an external power supply connected. On the card there is a directory named “MP3” with about 2000 short mp3 files.

I can mount the card and i see the subdirectories, in this case “MP3”. But if i use ListFiles there a only 585 files listed.
Now i tried to make four directories a 500 files. The result was :

“MP3_1” = 500 files
"MP3_2" = 500 files
"MP3_3" = directory not found exception

All cards are SD HC and 4 or 8 GB in size. The only working card is “takeMS” and the others “SanDisk, Kingston”.
I also tried to format the cards with the SD Formatter 3.1, but same result.

Has anyone a solution for this problem?
Thanks!

There was a bug when there is too many files. Check this work around:

http://www.tinyclr.com/codeshare/entry/200