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I'm daysichaining two ev3 bricks, and putting a color sensor on the slave brick, on reflexivity mode. The sensor is connected to port 1 on the slave. The sensor appears as connected, and mostly works, but sometimes it just returns the maximum value (128) for a while, and then returns to reading. How can I fix this? P.S.- the sensor returns 128 even when it shouldn't, e.g. I put it on black and it returns 128.