Recuva suddenly very slow

[Antiquarian]

On my old XP3 machine I have used Rucuva deep scan for many years. It usually takes 40 mins. Now suddenly it takes 18 hours. This was an overnight change, not some gradual decline. and no new software.

Everything else runs fine and I have virus checked and chkdsk 'd the drive defragged and tdss checked. 

It doesn't get "stuck" anywhere specific but is just dead slow throughout. 230Gb so no monster drive

I have even installed an old  version of Recuva contemporary with XP but to no avail so it isn't a "version" or "XP not supported " issue

I read about this problem often on the web some even reporting it taking literal days but no one ever posts a solution. 

Thanks