The noise will still be a problem.
The only thing you'll probably notice is a slight increase in noise. This is because ADPCM uses prediction and a predefined index of sample values. These predefined are used instead of the real value.
So if you have, say, 283, 999, 391 as the input, ADPCM codecs may make them 290, 1000, 400.
It sounds pretty good, but it's not perfect
