If the cappuccino maker is dirty or blocked the froth might have large bubbles.
Find detailed instructions on the guide below.
1.
Turn the steam/hot water dial to the 'I' position.
2.
After a few seconds, shut off the flow by returning the dial to the '0' position.
Turn the cappuccino maker anti-clockwise and pull it down to remove.
Pull it downwards.
Make sure the two holes arrowed in the image below are not clogged. If necessary, clean using a toothpick.
Push the cappuccino maker upwards and turn it clockwise into the nozzle until the two engage.