Time to get a new burner? (811s giving weird KProbe2/CDSpeed results)

So here’s the situation, I’ve been using my 811s for almost a year now, it’s worked very well (once I figured out that trying to write -R is pointless). However a few days ago I started getting “Power Calibration Area Error” during initalization with two different brands of +R discs (YUDEN000T02 marked as Fuji 8x and RICOHJPNR01 sold as Traxdata 4x) that have both worked flawlessly before. Nothing in my setup had changed, same hardware running Windows XP/SP2, same firmware (unmodified HS0K), not even a reboot between the last good burn and this new problem.
So I looked around, downloaded Omnipatcher and applied HS0R with recommended media tweaks. First three discs worked just fine, then I started getting some weird results in Nero CDSpeed (see attached JPEG). Read speed starts off around 2.4x then makes a quick jump up to something like 3.70x and then gives a good arc for the rest of the test. I read about CDSpeed and KProbe2 PI/PO tests and tried those out as well (see attached PNG). As you can all see, the PI reading reaches past 1400 at 4x and peaks at 311 at 1x. If I understand what I’ve read correctly these values SHOULD mean that the disc would be hard to read, however as far as I can tell all discs that display this behavior work just fine in my stationary DVD.
Can someone explain what’s going on, and perhaps give me some suggestions as to what remedy I can use? I appreciate all input. Just because the discs SEEM to work doesn’t mean they’re good discs, and I don’t want to waste more discs than necessary.

By the way, I’ve tried using unmodified HS0R as well, gives the same results.

Many (but not all) 811s drives give very bad results for a Kprobe scan run at 4x. Try scanning at 6x with Kprobe, see if it doesn’t look much better.

I tried 6x (see attached PNG), pretty sure it ran at 2,4x though. That’s what “Current speed” said throughout the test, and the 25 minutes it took to do the test would confirm that right?