The only one I find curious is the 3dB difference in the center channel. Plus or minus 1 dB is a reasonable difference and could explained by any number of small factors. But, +3dB is not so easily explained.
Is the meter placed where you normally sit (the sweet spot) and at approximately the same height your ears would be? What are the distances from each speaker to the meter's microphone? How is the meter pointed - straight up, straight ahead (toward your TV screen) at a 45 degree angle, or aimed directly at each speaker as you rotate the tones? Are you holding the meter in your hand, or is it on a tripod or propped on something? Are you ensuring that your body is not reflecting any sound to the meter?
