I have tried all the suggestions of setting it to zero and clicking up once on my phone, on the laptop, on the speaker. That setting is too high at times. This seems like something that would be very simple to fix in the controls. It has been raised quite a few times over the years as well.
Best answer by Airgetlam
There's been other requests for such a feature. As a guess, Sonos will add your name to the list of people who have asked for this. Someday, the request may bubble up on the list of "these million things that have been requested" to a level where they will implement it.
Some people have had a moderate amount of success by using the limits that you can set on the speaker, to keep if from going too loud, but I don't think that adds any intermediate steps to the current volume, I think it's more a high end limit, rather than a compression of all volume levels. Certainly worth taking a look at in any case.
One of the issues is that on an electronic device, there a "step" where there has to be enough energy to push the electronics enough to have sound. What I don't know is where that level is, and whether it can be adjusted.
You may also want to try 'tapping' to the left of the volume to get some finer control on it stepping down.It's apparently easier than trying to drag your finger.