Buffer Over run

I have twice tried to write some avi. files as data to a DVD disc using Nero 7.0. I have now made 2 coasters. The first time I saw that the writing speed was 12X on my Pioneer 109 with 1.58 firmware and assumed the problem was too much speed. The second time I saw the speed was 4X but I got the following warning :

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Buffer over run detected
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C:\Program Files\ core\nero.exe

Buffer over run detected corrupted the programs internat syate. The program cannot safely executing and must now terminate>
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Any ideas as to a solution??


Thanks