Corrupted data!!

I have just purchased a Sony 1GB card for my Japanese PSP fw 1.50

Loaded up some stuff onto it ,but all I get is corrupted data.

Loaded a digital photo ...corrupt
Loaded Fastloader....... corrupt
Loaded an MP3.....that worked OK

Tried formatting through the card reader ,started but said it could not complete the format .
Have formatted and reformatted a few times in the PSP , same results.

Have I got a duff card?

Seems to work OK if I connect the PSP direct to PC .
Using the card reader seems to be the problem!