Nothing to worry about, IMHO.
From Plextors documentation:
[I]What the Jitter Measurement Means
The data on the surface of a DVD or CD is expressed by pits burned into the recording dye, and by unburned areas, or lands, which represent the 0 and 1 binary bits of the computer data. The CD book standards prescribe these 0 and 1 pits and lands as a series of 3 to 11 pieces in sequence (described as 3T to 11T). The millions of 3T data segments on the recorded media actually have minute variations in length, with practically no individual 3T segment matching another. This variation distribution is called the â€œjitter ratio,â€ and is a measurement of the variation of the prescribed length of the 3T segment against what is actually written on the disc. A lower jitter value indicates better uniformity of 3T data, which means the recording is of a higher quality. The book standard regulates jitter value at no more than 35 nanoseconds. Using PlexTools Professional and the Plextor PX-712 or Premium drive, you can use the Q-Check Beta/Jitter Test to determine the quality of writing on a disc. The test graph displays an average rate for jitter occurring between 3T and 11T. When you select the sample length, you actually specify a range of addresses that represent anywhere from 15 seconds to 5 minutes on the disc. The test lets you evaluate the relative amounts of jitter in different media brands, or compare the results from a specific media brand recorded on different drives.