Blend node not compiling is it Enum?

I have a small patch where I have a Blend node Ex9 Effect that doesn’t seem to want to compile when I open the patch. I can delete it re-attach it and it works. It seems to be a problem with Enum, I get this from the TTY
([event:call: error occured in Enumnode](event:call: error occured in Enumnode):)
Zugriffsverletzung bei Adresse 0252DBD3 occured in ]: Zugriffsverletzung bei Adresse 0052E6FC in Modul ‘vvvv.exe’ Lesen von Adresse 00000030

which scrolls continually up the screen.

Anyone shed any light?

Should I switch the Enums somehow on startup?

How would I do this?

Thanks

stu