Debug Variable tab "no local variables.... "

I've seen this off and on, but it was never really a problem until the
other day.

During RPGLE debug, with the debug paused. I can view the contents of
variables by mousing over the variable name in the code or if I add it to
the "Monitors". But the "Variables" tab just has "no local variables are
available for the selected stackframe".

I assume stackframe is the selection in the "Debug" tab, I've tried all the
programs in the stack and no variables show on the variable tab for any of
them.

So far I have done the following to try to correct it:
1) Upgraded to RDI v9.6.0.10
2) Found a reference to PTF SI73597 (v7r3) which has now been applied.
3) Stopped and Started the debug server (and TCP (*DBG) server)
4) Rebooted Windows PC
5) created a new workplace in RDi and still have the same issue.

Not sure what else I can try next. Usually it's not a problem, but the
other day I was trying to debug a SQL issue and I could not remember the DS
name that SQL uses.

Thanks