Avios Grand Tundra plus

I have a Avios Grand Tundra Plus which I got on Friday the 12th June 2020 from the UK warehouse and in straight level flight it will suddenly dive or roll has anyone had the same fault or any idea what it could be ???? I did manage to land but did brake the prop , but lucky to be in one piece .

Running all new 6s lipo4000mah , New spektrum AR8000 with sat ,the rest is as it came .

Kind Regards

Ian Pope

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