PCE CD - (USA) 4-in-1 Disc - Sound error

[GoogleCodeExporter]

Using the the (USA) 4-in-1 Disc that has Gate of thunder, bonk 1, bonk 2, and 
bomberman.  If selecting Gate of thunder a sound effect occurs and the emulator 
then continues to linger the sound longer throughout the games menu until you 
select a mode to play.

Original issue reported on code.google.com by pasky1...@gmail.com on 5 Jun 2012 at 9:39

[alyosha-tas]

Ok, so the audio in that section is controlled by the 6280 timer. If I make the timer tick slightly faster, or I give slightly more CPU cycles per frame to work with, the bug goes away. now I just need to figure out where the error in the current set up is that would allow one of those 2 things to be true.

EDIT: It looks like about 15 cycles per scanline extra for the timer to tick is needed for the problem to go away. This equates to about 9 scanlines worth of time that the CPU must lose somehow, either with RDY low or cycles otherwise lost somewhere.