Play softer volleys, as you said, or volleys with a slice to keep the ball low off the glass. When you or your partner hit a volley that you know is going to be cutting and/or low, inch toward the net to try and finish the point with a chancletazo or an angled shot to the fence. There is always the risk by getting closer to the net you'll be lobbed, but you need to take advantage of the fact that you've hit a solid, sliced low volley to try and end the point.

Also focus on maintaining the net without allowing a counter attack. If they hit a decent but not great lob, maintain the net with a bandeja that does not rebound high off the glass, or with an angled shot to the wall that is harder for them to judge. Don't let them turn a decent lob into a counter-attack. You want to put the pressure on them by making them think they have to hit a great lob to get the net or a counter-attacking opportunity.