I unzipped and installed the sample application and set running. On clicking the start wav visualisation, it immediately throws an exception when starting the thread.
The screen dump and log window show the error:
I am struggling to understand why it can't open/use the DrawWav Sub which exists.
This is a really old example, which you are running in Obsfuscated Mode. Subnames called via String literals need to be renamed to include an underscore which will stop them being changed.
No, the working code is still sound, but the use of Threading is not compliant with current promoted practices. It would normally be replaced using a Timer or Loop with appropriate Sleep statements that do not tie up the GUi thread.