Hello Chris and Pearl,
Have you checked to see if you have other devices connected to the TV that can have their own volume controls and can cause the TV to have low volume if their volume settings are low. Some cable boxes can have such controls, along with standalone DVD players or DVRs.
You might also try a soft reset of your TV. Unplug it for a minute or so and press the power button for 30 seconds while it is unplugged. Then plug it in again and see if the volume works better.
You might also try some of the items on [[Samsung TV Has No Sound|this page|new_window=true]]. Although it applies directly to Samsung units, many of the checks can apply to to other brands.