THIS IS THE ANSWER!

Thanks Dalchina. The issue is caused by the Realtek audio driver file FMAPP.EXE which needs to be renamed to prevent it executing. More details at...

I can confirm this Realtek fix also solved the mouse (and trackpad and trackpoint) lag on my Lenovo Helix.

THANKS!

I have used the task manager performance monitor to check the CPU and disk activity during the issue and I see low levels of usage for all parameters.

However, as an earlier person noted, when...

I am using a wired USB mouse and touchpad and am experiencing serious cursor lag as the other people above, following a windows 10 upgrade.

the lag comes and goes intermittently, with no obvious...