I have never been able to flash new firmware. Now that 3.2 is out I really want the new position hold mode. When I go to install firmware in mission planner I select 3.2. It goes through detecting board version, then reading hex. The bar starts to fill up and goes till about under the 75% point, then it stops and flashes up an error box "communication error- no connection". My cable and everything is fine. I have been using the same cable to monitor telemetry and program my apm for months without issue. What should I do?