Sorry but this issue most of times is due to a bad quality disc, so I blame the media.

Try again with a proven quality media, like a Verbatim. This should solve

Maybe you can try to burn at a little lower speed, but a crappy disc cannot be transformed in a good disc by any burner.

I really suggest to not burn any important data on low quality media. Most of times low quality discs become unreadable after a short time