"128kbps is about 145 hours of music on an 8GB, maybe a bit less.:
I figure around 18 hours of music per GB at 128 kbps. So that works out to around 144 hours. If the songs average 4 minutes or less, then you should be able to put at least 2,000 songs on the player.
Try formatting the player using the format command in the player menu. Set the USB mode to MSC. Connect the player to the pc, and let it charge fully. Download the latest firmware and extract the file, and drop the file to the root of the player. Disconnect the player, and let it do the fimware update and power down on its own. After that, connect the player, then use Windows Explorer to copy and paste folders of files to the player.