CF Reader saving problem(a-z partitions)

Hello I have a mpc 3000 fully upgraded with 3.5 valixi and CF Reader and the problem is when i save my programs and sounds on partiotion A everything is fine
but when i try to save something on partitions b,c,d,e,f etc it wont save all my files( and says ''stop using this partition'' some sounds are saving fine though, but some not. The card is sandisk ultra II 1gb and on every partition i have around 25mb (24608k) free space Whats the problem? my CF reader looks exactly like this one:

My CFreader is from scsiforsamplers.com

A partition is working fine, B works hmm.. good but wont save everything sometimes and the other partitions works for saving sequences and small sounds, shouldnt i be able to save as much i want on every partition? I get errors when trying to save bigger files ''Stop using this partition'' The Valixi 3.5 is original ordered from mansel-labs

Try a different CF card.

Do u have any idea wich cards should work fine with my reader?

no