In this specific situation the real bottleneck is not the high amount of traffic for the USB bus, but the too slow speed of the flash drive.
Even if buffer underrun mechanisms will allow to burn anyway a disc, I personally prefer to avoid too much buffer emptying. The best option is to burn files from hard disk
Maybe with a scan you can see how much errors there are on that disc. Do you have a liteon burner?
btw, if the disc is readable, unless you are using a very low quality disc that will degrade quickly in time, there should be no problems