This problem started when I upgraded by Img burn to a new version.
Normally the verify speed would be around 15-16 in the end, depending on how big the image is.
I have tested multiple brands dvds but I know its not the dvd itself.
If I use img burn 184.108.40.206 or dvd decrypter last final version, no verify speed problem found.
I have poked in the setting and the Img burn I use now is 220.127.116.11 says max verify speed for data/audio in the log.
I have tested the quality as well and its very good burns indeed.
I have benq 1655 and 1640 but like I said dvd decrypter or img burn 18.104.22.168doesnt show any problems.
Verify speed now with img burn 22.214.171.124 is never above 12 and then when it get close to 12 its drop like a stone in the water to 7-10, then it fluctuate between 7 to 12. If I didnt know better I would think that I'm burning a dual layer disc even though its a regular dvd-r or dvd+r