I'm reasonably convinced that there is a problem in the players eq code where channel lock appears to set the 2 channels differently. I want to sit on the fence until I can get a white noise input and a scope on the output, but looking at the numbers that the player sends for the frequency and q factor suggests that there is a bug, and someone posted a rather bizarre graph recently that would appear to suggest the same.

If you keep to flat eqs then there wont be any problem as the gain bits are kept in sync.

I'll keep y'all posted as to anything I find out.