I'm pretty sure that the "player" executeable does the "remount rw" operation during the "synchronize", and that's the part that is messing up for you here. Pitty the software isn't just a bit more clever about things, but it is not, and we don't have source code to fix it.

So, you'll have to hack the kernel -- just have it check the process name of the caller to "sys_remount", and silently fail /dev/hdc4 whenever the process name is "/empeg/bin/player". This test can be done as:

    if (!strcmp(current->comm, "player")) {

        // player software is doing this call

    }

Cheers