job, that is very strange, I have never seen this before. You could try to extract the firmware from the bad player, repair it and then load it back on, this sometimes fixes small problems like this.
To extract your firmware you need s1fwx
HERE and there is a guide how to do this
HERE .
If that does not work looking at the two versions on the two players you might be able to extract the firmware from the good player and load it to th bad one.