
@peacer, not sure what it could be. The game is loading perfectly, as it boots and also the wav is using the crc checking every 256 bytes, so if the game auto runs, it's been loaded without errors.
I'd bet you are right about the program failing to detect the vsync hack. And I am not sure why. The only thing is that the hack plugs the sync signal through the tape-in, and the auto detection tries to detect pulses in that signal. Maybe your player generates some kind of signal in the tape plug when the game finishes loading which, in turn, is detected as the sync signal.
When the text is plotted, each letter is printed after waiting for an sync, so this kind of noise or signal keeps lasting for a while.
Not sure. Have you tried loading using another device, such as a PC?