Swap taps. If the problem moves with the ale, then it probably is over-carbonated or the poppet valve has a problem. If the problem stays with the line, you need to dismantle & clean the tap and clean out the lines.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
"I would like to die on Mars, just not on impact." Elon Musk