What make of panel is it? The differential controllers and pump station usually come with a 2 year warranty and most panels come with 5 year warranty. Kingspan give a 20 year warranty on their panels when they are installed by an accredited installer but only 5 years if not.
It would be highly unlikely that the panels are at fault unless they were idle for long periods. Usual culprit is microscopic air in the system has built up and the pump cannot shift it. Purging with a pump station is the cure but a full service is a good idea at the same time. This involves setting the correct flow rates, checking and setting the expansion vessel pressure, etc.