You need to tell us which player and how much memory it has and preferably what bitrate your songs are ripped at, all of this will have a bearing on how much can be stored. That being said, 2.75 hours seems very little for any modern machine.
sorry folks for not giving you enough info, i´ll have a look at the book that came with it later, as theres nothing else to tell you from looking at it, apart from its called a LEOTEC, and it has 4GBFM written on the back.
Do you mean 2 3/4 hours of music videos, or just music?
If just music, then it sounds like you are ripping to an uncompressed format (such as .wav) instead of mp3.
at 256Kbps you should get around 32 hours on your 4 GB player.