That's not to bad,when there up over +/- 4 or greater all the time then that specific injector may need replacing. Try running fuel addictive like stanadyne.replace fuel filter. Then check again
I run 2 stroke oil regularly. Most of the time the balance rate for #4 is 2.4-2.5 but sometimes its high like above. Just didn't know where it begins to cause problems or become noticeable.