Unresponsive cursor when USB 3 drives connected. The fix is weird.

So.…..

I have these three USB drives, one a Seagate portable, the other one I made from a USB caddy and my old Dell drive (which was replaced by an SSD), and the third is a SanDisk flash drive.

Whenever I plug any of these into my Dell laptop the cursor under mouse control becomes unresponsive and laggy (very juddery and often unusable). The touchpad remains smooth and responsive. The mouse is an HP Z4000 wireless one.

Well the cause is an odd one. It is the mouse mat. Yep, you heard right, its the mat.

The mat in question is a faux white leather one, and very nice it is too. However it appears to be the cause of the freezing/juddery cursor when USB3 drives are active. If I move the mouse to a dark surface all becomes good and all problems disappear. Back to the mat and the cursor is freezing again.

With no USB3 drives connected, or with a USB2 drive, all is good with the white mat.

How weird is that :) I can only guess that the white surface reflectivity/quality is marginal and that in normal use the USB port devoted to the mouse receiver gets 'full attention' with regard to any error correction and data flow. When the duties are split the problems surface. The black surface must be much easier on any error correction and data rates to and fro. That would be my best guestimate anyway.

It certainly is an interesting one, and one that ranks up there with the best of the weird faults I encountered as an electronics service tech.