Thanks for all your help.

1.Reset to factory settings = No change
2.Uninstalled K-Lite and installed K-Lite Mega = No change
3.Update 471 installed over existing = HOORAY ! all working again !

I don't know why this happened because I have converted to MP3 SINCE the 471 update in December with no problems.

The mysteries of computers !!!!

Thanks again for all the suggestions


BIAB 2017 Everything, RB 2017
Lenovo All-in-One. i5, 8gb Ram, 1 TB SHDD, Windows 10
Presonus AudioBox,Studio One 3, Behringer Xenyx302,
M-Audio Axiom 61, Samson Graphite 49.
Lenove Flex 15, i3,Windows 10