It is possible that the channel is being broadcasted at a reduced power. Repeater or translator stations usually have low power outputs, as do TV stations with Class A LPTV entitled to greater interference protection. Some stations run lower power for economic reasons.
The majority of TV stations transmit on UHF frequency. However, some broadcast using VHF. While some antennas pick up VHF signals, it is necessary to use an antenna optimized for UHF or UHF/VHF frequencies.
Changing the location or elevating the antenna could also resolve the problem. If you’re having trouble, give us a call.