It sounds like the CB-8269 was not making good contact with the UHF wires when it was in the housing, the board is defective, or it's the wrong board. I've never been impressed with their arrangement for combining VHF and UHF. Why don't you call their customer service tech.
Customer Service – RV, Truck, Marine and Home Antennas
Phone: 800-288-8094
Fax: 800-247-8221
Hours: M-F, 7:30am – 5:30pm CST
http://www.winegard.com/consumer-contacts