Lyrik 2-Step

I know there has been quite well documented problems with the 2-Step spring in the Lyrik and they tend to say the problem is with the travel adjust failing in some way ie it stops going down or you have to pull it to re-extend to 160mm. But I havn't found anything that tells me what is actually causing the problem and what RS do to fix it.

Is it a simple case of o-rings wearing out or a standard service part needing replacing early on or is it more serious than that.

Basically what I'm saying is can I fix it. I'm considering buying one but am worried about their history and while I am a competent mechanic I don't have a machine shop at my disposal or a shed load of money to keep paying for it to be fixed. Has anybody taken one apart and found out what is wrong with it?