Ensure that there are no headphones plugged into the globe's headphone port and that the volume dial is turned up, if you do not hear any audio originating from your globe's speakers.
Check that the globe's batteries are properly installed and aren't drained, if your globe's audio is distorted. Also, check the batteries if the globe doesn't power "On." Use a screwdriver to open the globe's battery door.
Ensure that the battery contacts are clean and that the batteries are set to the proper polarity. The positive and negative ends of the batteries should be orientated with the (+) and (-) markings inside the globe's battery compartment. If the batteries are properly aligned and you still have power issues with the globe, remove the batteries from the battery compartment.
Check the contacts inside of the battery compartment for foreign matter. Older batteries may leak acid onto the batteries' contacts -- in which case, the contacts will need to be cleaned and the batteries replaced.
Dampen a cloth with rubbing alcohol, and then use the cloth to clean the foreign matter from the contacts inside of the globe's battery compartment.
Replace the globes batteries, and then attempt to power the unit on again. If the unit powers up, then use your screwdriver to secure the battery door to the globe's battery compartment. If the globe still doesn't power "On," replace its battery with new ones -- don't mix old and new batteries.