We just upgraded to 1.2 and have a dongle attached and still we are going to eval mode, but only occasionally, not all the time. We have tried different USB ports and still does not make a difference. The only thing that helps is re-booting from scratch again and even then sometime we still are going into eval mode.
Have you tried contacting the partner that sold RMS to you. They should be able to help you with this. The USB dongle can be pretty touchy. The USB drivers have to be a specific version or it does not connect properly every time.
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