Well done! Even no changes is a good finding
Now you can eliminate certain part of data.
so CC >CD
when I played again,
it just changed the song title text that shows in beginning.
it shows as ttinkle twinkle mittle star
song text displays fine.
I am still not clear what we looking for changing the bytes value,as I am not expert in karaoke decrypting
It's not just about the values. It's also about the position. If you don't provide enough information it's very hard for me to give you advice. Please READ the thread California Electronics (I've given you the link above) and post your findings in a similar way.
Following things you can do next:
1) Patch the same bytes (e.g. +2 and so on) to find out the mask behind that because 'w' -> 't' and 'l' -> 'm' showing different behaviors.
2) Patch the same position in another song and find out whether the title is stored in the same spot.
3) Patch other part to find music and lyrics data.
Okay, maybe you haven't done programing before. So it's hard for you to do the reverse engineering.
btw, one hour is nothing, have a look how long that thread dragged along. Last time we even had to burn on a re-writable DVD each time to test our patches