iPod Classic won't turn on at times, plus other issues

Hi fellow ifixit users,

I've had my classic for about 3 years now and i've been running into these issues recently:

1) When disconnected from PC, will not turn on

2) When charged, either by wall, pc, or car, I'm presented with constant flash (on and off showing the apple icon). If I toggle the "HOLD" on it stops the flashing and the ipod shuts off.

3) Sometimes my pc does recognize it (shows the connected message with the orange and black icon) and I am able to sync it with itunes but once I disconnect it again, it shuts off completely.

4) When my ipod is my "Cygnett Sports Armband" case at times it will shut off, when I have it on hold while running music. (I think this is a result of the ipod being so tight against my arm)

For solutions I've attempted: restoring my ipod from itunes and doing it manually (toggling the HOLD button, holding down the proper buttons to shut off Ipod and shut it on, etc..) but nothing has worked so far. I'm starting to think I might need a new battery.