Help GT-I5500 no notification sounds?

Hi, I hope you can help. A week or so ago I had trouble with my phone saying that the memory card had been unexpectedly removed (when it hadn't), it did this a few times before I removed the card and cleaned it.

This seemed to sort the problem but ever since I've had no notification sounds, I've gone into settings and even though I can scroll through ringtones just fine, if I go to notifications I cannot preview them.

I have even copied sounds I have listened to on the phone to the notifications folder on the SD card but when I go into settings to choose it, no sound is played.

Can anybody provide a fix for this problem?

Thanks in advance