1. You must first calibrate your battery, to do this, you must charge it completely, then drain it all the way, and recharge again.
2. Audio equalizers can reduce battery life.
3. Multiple clocks can also reduce battery life.
4. And most of all, backlight reduces battery life.
What quality audio are you using on your 5G? Remember, if you use a higher quality than the 128kbps Apple quotes, you are accessing your hard drive more often and so therefore also using more juice up.