Hi,
Try cleaning house on it.
Also Try the Garmin web-updater
Here to keep it running well.
You could wipe all data and start again,
Backup anything you want first.to the Pc....
Hold bottom right of screen, keep pressing until it says,
Do you want to erase all data, erase it, select yes,
Re-register with Garmin, re-update,
Your good now,
Regards