Upgrading to Tiger resulting in jumpy mouse

Question

I've searched through the forums with little success, although I may have overlooked a similar topic and apologize if one already exists. I'll try to keep it as simple as possible. I have a Graphite iBook Firewire SE - 466MHz. I've already upgraded the RAM to 576MiB (maxed), replaced the DVDROM (it was all but dead anyway) with a UJDA740 Combo Drive (using PatchBurn to enable the burner functions), and put in a fresh install of OSX 10.3 (after which I fully updated all of the software). I recently decided to undertake upgrading the hard disk in preparation for installing a Tiger upgrade (not a full install, just the upgrade version). The hard disk that I chose is an 80GB Western Digital Scorpio. The upgrade went well, and Panther reinstalled perfectly. After installing all the updates, I installed the Tiger upgrade. Again all went well. This is where things get odd. After fully updating Tiger, my 'Book now has an unusual quirk. Everything works fine until I use F12 to eject the optical drive. At that point the mouse acts as though it is having trouble tracking my finger .. almost like an old mechanical mouse that has become clogged with dust and dirt. External mice don't exhibit the same problem, and a quick 'Sleep' mode will snap the trackpad out of it. I thought of it possibly being a hardware issue, but here is where it gets really weird. I can click the 'Eject' button in the bottom right corner of iTunes with absolutely no ill effects. I went back and did the installation and upgrade of the OS all over again and found that the problem crops up as soon as the 10.4.11 combo update is installed. Any ideas as to what could be causing this and how to correct it would be most appreciated. I'm not a computer genius, but do not mind getting my hands dirty (i think upgrading the hard disk says it all).

Answer 1

I'm a persistent type AND a glutton for punishment, so I'll jump in on this; I (as you) would like to get to the bottom of it.
Up to a few weeks ago, I had no experience whatsoever with the clamshell iBooks, but a relative asked if I could retrieve the hard drive contents of his non-working (300 MHz) tangerine. I was able to remove the drive and use an enclosure to transfer the contents to my desktop, from which I made a data DVD for him -- and that was to be the end of it.
But I became intrigued with what might be done with this computer, so I obtained a 512 MB memory card and a 120 GB drive. Before I re-assembled the unit, I partitioned the new drive and installed his original (9.1) OS -- and a clean install of 10.4.11
Using a replacement AC adapter (the adapter he had was the original problem), I was pleased (actually amazed) that the unit booted up quickly in Tiger and actually ran pretty well. The single intractable problem, however, has been the trackpad. Although it works, there are scenarios where it becomes unstable (or jittery) to the point of being virtually unusable. Those scenarios are (and certainly there may be others):
• iTunes (the worst offender I've found) running.
• Right edge of right hand on or near top cover while manipulating the trackpad with one finger.
(The edge of the hand is touching or near the computer cover, not the trackpad.) Misbehavior is much worse when offending apps are running. This seems to be totally absent with the left hand in a comparable position on the left of the trackpad.)
The nature of the misbehavior is this: although the cursor can be positioned with the trackpad (and speed is normal), as soon as one's finger is lifted to go to the button below the cursor jumps off the target, sometimes considerably. If the hand is held well above the computer cover, this behavior is either reduced or absent.
I've briefly looked at this with two other OS's, 9.1 (on the same computer) and 10.3.9 (on another clamshell iBook). Although I haven't studied it in great detail, my sense of things is that although the described misbehavior may be greatly less prominent, it still exists.
The fact that the right hand (only) against the cover creates or exacerbates the problem is suggestive of a "regional" capacitive coupling effect, but in disassembling and reassembling the original computer two or three times I don't immediately see why or how the right and left sides of the computer cover would be different in this respect.
I've also considered the possible role of static electricity, although the humidity levels here recently have been so high that I'm inclined to think that's not it.
In some way that's not clear to me, this could be originating from an anomaly in the trackpad itself, perhaps something common to most of them, if not all of them.
At this point, I have these questions for contributors to this thread:
1) Is the "jittery" behavior I'm experiencing something you've seen? (Sluggish behavior is not something I've seen.)
2) If yes, does it only occur with 10.4.11?
3) If yes, do you think it's totally absent with other OS's?
Thanks for any additional information.
Message was edited by: osimp