Whats new in 01.01.05a ?

I have Firmware 01.01.05A installed. I have 2GB Sandisk MicroSD and 4GB SDHC Sandisk MicroSD. The music folder on the 2GB is read no problem but the same folder on the 4GB is not read at all when the Sandisk Express builds the music database. In the settings this 4GB Sandisk MicroSD is recognised. What is the reason for the player not reading any music files from this 4GB microSD?