Sometimes it jerky ...

I have my first Saitek Mouse acquired years ago, the same model, but much more robust. I wanted to I purchase a second mouse for work, but this seems to clearly bucking (another model had this behavior also). The backing was a blue-green-white Mouse Pad (plastic surface, no substance), on which the old Saitek mouse moves beautifully. Both new mice showed no jerky behavior only on white surface (A4 paper). Saitek what's going on with you?