The clock in my 2005 S40, which I bought a few months ago, really keeps terrible time. For awhile I would see it had gone a minute or so slow every couple weeks, but just kept figuring I hadn't set it exactly right. I hadn't paid attention to it for a month or so (guess I was never in a rush to get anywhere) but today realized that it was about 8 or 9 minutes slow.

It just went out of warranty a few weeks ago, so I doubt I look into this too deeply unless it points to something else more serious.

It kind of bugs me that a cheapo knock-off watch can keep better time than my car, though.

I never use the volvo clock... but can be a problem with the crystal.

same thing here, the clock, computer quartz must be of bad quality, not very acurate.
I have not gone in the trouble to ask my dealer.
Greg

known fault that can be repaired.
Set your clock and time exactly how fast/slow it is over a period of at least a week and take this info to your dealer, they then will be able to adjust the clock speed to solve the problem
In extreme cases a new centrol computer will be required, but most unlikely.

changing the quartz crystal fix the issue but maybe they will want to change the full computer.

No! slowing the clock down or speeding it up a few seconds a day via the computer usually solves the problem.

He can try that but if not works the quartz is bad.