There are some considerations.
First of all, is impossible that you have a quality test in only 31 sec; for a full dvd are necessary about 12-15 min. In my opinion, the test was aborted. I'm not entirely sure about this, but probably cd-dvd speed don't work correctly on all external burners. Try to do a scan with an internal IDE drive.
When in this forum someone refers to a "scan", it says "disc quality test".
For a forum standard, must use 4x when scan a disc.
Moreover, ritek are very variable in quality; some batch are really good, and other are coasters. Try another media (verbatim or, better, taiyo yuden).
Finally, after the scan finished, hit the button on right-upper corner of the window (with a little disc on): in this way you can save the image of the scan and can post in this thread. Choose to save in .png format (file size are little and image quality is good for posting on the forum).