shef , there isin't a 8GB chip installed in your player in the first place. i'll do suggest that you perform a proper format using MP3 Utilities Disk Tools, guide is here
http://www.mympxplayer.org/how-to-re...ck-vt2400.html
If after the format, you still end up with 1GB, then likely your player only had a 1GB chip hacked to show 8GB instead. You can't recover the lost 7GB, because it does not exist at all.