Note that a bug was recently found in Emacs 29 relating to byte
compilation which was generating this error. Apparently it also causes
problems with backwards compatibility of *.elc files.

Not sure if it has been fixed in Emacs master yet, but my recommendation
would be to do a git pull for Emacs, followed by a make extraclean,
./autogent.sh, ./configure and make and then a rebuild of any additional
packages you have installed.


Tim thanks for confirming that this may be an issue with the latest Emacs version, I will try what you suggest and also see if I can track down the related byte compilation bug. 

Regards
Darren