Distorted Audio in laptop speakers and headphones

Not having much detail and assuming both channels are distorting, I can venture the following:

Audio distortion can be due to a number of factors

1. Turning up the volume to a point where the load (speakers/headphones) can't handle the power can cause AF clipping (distortion).
2. The built-in amp is being overdriven IOW not enough power to handle the volume
3. The built-in laptop audio amplifier has a component (such as a Capacitor for example) that is intermittent and will cause distortion under certain conditions (overdriving, overheating, Age)
4. So, this sounds more like a HW problem. I am assuming the laptop is a number of years old and was acquired when XP was still the go-to opsys
5. A common way to test (if you are able to get at the laptop's innards) is to induce or wait until distortion occurs and then apply a freeze-it spray to where you suspect the AF amp and components to be. This most likely will be an IC but with larger output capacitors usually mounted as discreet components on the pc-board itself. If the distortion dissapear you may have fingered the culprit.