Button was sixth-fastest in P1 but then dropped to 10th in the second session. However, the Brit said that the feel of the car is improving.
"We tried a number of different set-ups this morning - but I think our baseline was in the wrong place, so they didn't particularly work around this type of circuit," Autosport quotes Button as saying.
"So we reverted to more of a traditional set-up for the afternoon, and we developed the car over the course of the day, so we're now getting there, despite the setbacks of the morning. In a way that's positive, because it meant that we'd already been getting the best out of the car for the whole year."
Sebastian Vettel was fastest in both sessions and is expected to wrap up the title this weekend.