Is anybody else having communication errors with their Tamron 24-70 G2 and a Red camera-- in my case a Red Epic and a Canon EF mount? Problem I'm having is that the camera with the lens attached only boots up with no communication issues half the time. When there are comm. issues the aperture readout reads "N/A." I'll then have to shutdown and reboot and it usually works then. Another issue I have is that the F/stop functions fine and then will turn yellow with non-sensical f/stop numerals -- "f.07 or .10." This is the second G2 copy I've had after exchanging the first with a replacement. Lens works fine on my other cameras.