Do you have a Jura Z6 or Z8 and find that the milk will splutter sometimes even though the frother is clean?
There are a number of causes, and we will try to list the things to check here:
First, and most important make sure all components of the frother are clean and fitted correctly as any debris will prevent milk flow and any air gaps will let in air in place of milk.
You should also check your milk container as milk blockages in the metal pipe in the glass milk container or cool control can restrict flow. If necessary, remove the milk container and feed milk directly through a pipe so as to eliminate this possibility.
If you have not already replaced the foam nozzle in the last 6 to 12 months, it would be a good idea to replace it to rule it out (link below):
Then, in the settings, make sure the milk temperature is no higher than 8 - as the range runs from 1 to 10, any temp above 8 can restrict the milk flow too much and result in spluttering.
If the flow is good for a moment then starts spluttering, try gently pulling with a single finger on the back of the inlet hose (see image). I found that even with brand new parts of the frother and parts inside the machine we were still getting the spluttering. Just pulling on the hose for a moment should settle it down into a nice smooth flow again.