Do you reduce your in-game sensitivity a lot to over come your extremely high dpi setting? Most most mice, even ones that claim up to 12000 DPI don't track well over 1000 DPI and start developing issues when set above that. The issues can very from acceleration to jitter. I would try a setting of 1600 as a starting point if you want high sensitivity. I am not positive about the DPI scaling for the Avago 3888 sensor used in that mouse, but you should be able to adjust the DPI in at least increments of 200 starting from 0 and not get any artifacting. So try settings of 1400, 1600, 1800, but definitly not the max of 3500.
If decreasing your sensitivity doesn't solve the issue I would also look into the classic "tape fix" for LOD issues. I know that some of the Deathadder which use the same sensor had issues with LOD.
LOD Tape Fix - http://asiafortress.com/forums/index.php?/topic/1583-tape-fix-for-lift-off-distances-of-all-mice/