Check the connector to the battery pack. Looks like a 9 volt battery plug. Also could be the actual plug/connector on the battery pack. Have seen some that have had batteries left in them, causing corrosion and bad connection. Even saw one that had a terminal that was corroded enough that it fell off battery pack. But this dosnt explain clock not working. Best thing might be to send them back to ON-Time and let them check them, they do have a lifetime warranty which they stand behind. All you have to pay is shipping. Have five myself, four that are 12-14 years old, would have no other brand.
My Yote toys,
DPMS Sweet Sixteen
Ruger 77 22-250
Glock 23 40 cal
Foxpro 416B & numerous hand calls
God would never send Firefighters to Hell because we would put the fire out!