battery
Is it normal and expected for the battery on my ipod classic to drain fast while not in use even though the device is off or in sleep mode?
Question marked as
You might consider replacing the battery. I've done this with a number of 5th and 6th gen. classics. You can get the parts on Amazon/eBay if you want to do it yourself, or you may find a third party repair shop can replace it for somewhat less than Apple would charge. See iPod Service Pricing - Apple Support.
tt2