How do you update the player's display?
If you have a track that shows the title allright, then the questions are:
is this really the contents from the field TITLE? This can be tested when you change the title and then see whether this modification is detected by the player.
The next question is: could it be the filename that is shown? What happens, if you rename the file (a little with e.g. an added underscore)?
Is there a cache or database lingering in the background that needs to be updated?
Then: what kind of files are these? mp3? flac? wav? other?
if mp3: what kind of tag versions do you find in the files? just id3 or APE as well?
Are the file OK? Perhaps it is worthwhile to test them with the tools linked in this thread:
What does the manual say about the features of the player? does it support the file type and tag type that you use?
And coming back to the original idea of overlaying the picture with tag data: