Mouse problem

Since July about every fourth boot on my XPS 420 my optical mouse light goes out after windows loads and the pointer freezes.  On the restart it usually stays on and operates normally.  When it fails to operate I can use my wireless laptop mouse, so I assume it is hardware related.  I have tried changing USB ports and that seems to make no difference.  No help from India, where they don't seem to know the difference between an optical mouse and an optical drive.  Anyone else have this problem?