Why aren’t the volume presses synchronized between my iOS device and my MEGABOOM?

The volume on your iOS device and MEGABOOM are synchronized, but because your speaker has double the amount of volume steps, it will take twice the number of button presses on your speaker to reach max volume.

If you adjust your volume on your iOS device, there are only 16 volume steps, so from the lowest volume setting to max volume, it will take 16 presses. Your MEGABOOM has 32 steps from lowest to max, so 32 presses are needed to reach max volume from the lowest volume setting.