Bought a 2003 Volvo S60 used two years ago and love it. Recently I had noticed a loss of play in the clutch pedal, having a hard time getting it into gear. I watched the brake fluid since it's shared by the clutch and it seemed fine. There was no issues with the brakes and no leaks in the lines. Turned out the slave cylinder had failed, leaking brake fluid into the clutch assembly. Just got the car back today, $1700.00 later, works great. Hope this helps, had a hard time finding information about this problem online.