I realise this thread is old but I feel that my input here is needed.
I too have experienced this problem and after a good bit of looking, I found the source.
There was two files on my computer, one called beatvisualization.m
and the other called beatvisualization.maki
, the latter (beatvisualization.maki) appeared on the red text, black backgrond message on my computer screen.
These files are located in [DriveName]:\Program Files\Winamp\Skins\Winamp Modern\scripts
Since I love winamp, and I trust it well, I have left the files there, but also because I don't want to risk removing the files and messing up Winamp and have to re-install it.