Hi all, I have a M3 GBA expansion pack (well, 2 actually). The one I use used to work fine, but now it won't boot up any GBA games. Also, my spare one has the same problem. They are quite old (1 or 2 years maybe). I presume the batteries are dead. I plugged the GBA pack into my DS Lite and charged it overnight -- but still no luck. Do I need to unsolder the battery and replace it? Has anyone done this? Which size battery is required? Thanks for reading!