A few days ago i bought this famiclone from the mid 90s, its in the shape of an Super famicom, and i noticed that the console sounds strange, for example in Double Dragon 3 some of the soundtrack is skiped, or in super mario bros the dead sound is completly different.
This console is noac, and im using an 9v ac adaptor.
This is one of my glitched NOAC s. I do not think that there is solution for that kind of sound issues
https://youtu.be/hWEiAm7Ehzo (https://youtu.be/hWEiAm7Ehzo)
Nothing you can do, sadly.
Might want to check this: http://nerdlypleasures.blogspot.com/2017/10/nes-clones-reversed-duty-cycles-why-you.html