Q: Magic Trackpad Erratic Movement

I think that I found this today. Noticed over the last few days that every time I have the issue time machine is backing up. As soon as the backup is complete, track pad return to normal.

Is anybody else, apart from David Browning 'convinced' that this is a hardware issue?

From what I have experienced and read about in the iMac, MacBook Pro and Mac OS X v.10.6 Snow Leopard discussions this looks more like a software problem related to DL1066, 'Magic Trackpad and Multi-Touch Trackpad Update 1.0', posted July 27 2010.

I have a band new machine (two weeks old). It came with the "Magic Track Pad." I thought I was just an old man who was having a hard time adapting. But mine, from-time-to-time, exhibits one or more of the anomalies noted here. My daughter, who is also a MAC Driver, thinks it is a sensitivity issue. I can't tell if hit is a hardware issue, software issue, or temperature/control adjustment issue. But clearly, there is an annoying issue.

Could be hardware but not necessarily the Trackpad. I swapped mine over for another complete unit.. same issue. Wasnt the trackpad in this case and they were nearly 2 weeks apart so prob not a batch issue either?...

next theory ?

Oh ive since returned the second one of course. When we know a def. fix then ill rebuy
jas

I have an older late 2006 / early 2007 17" Macbook Pro - was experiencing very erratic and imprecise cursor movement. Tested w/ 1g macbook air and 2010 white macbook and Magic Tracpad worked perfectly so I ruled out wifi interference. Solution was simply to disable onboard BT and to plug-in USB Bluetooth 2.0 adapter (Asus BT21). Works beautifully now!

Based on the theory that it was a hardware problem, I swapped my MTP at an Apple Store (almost had to make an appointment at the Genius Bar since it was a few days over 14 days, but they took pity). The problem is less pronounced with the second MTP, but still there.

In my case it certainly correlates to back-up activity on Time Machine.

I moved the Time Machine away from the MTP. I found that putting it on the floor several feet behind the location of the MTP worked best. This seems to have eliminated the problem for me. So far.

I spoke to soon. It is better, but still some drunken behavior when Time Capsule is backing up.

My mac pro was late 2007 too
Maybe it's due to an earlier implementation of blue tooth or an earlier BT transceiver version in macs made back then???

Not sure if this affects the MTP, but I've had several blue tooth devices stop working and act erratic if a microwave oven is turned on.

Same issue here. It works for 2 seconds after I power it up, and then the cursor goes crazy. I tried everything: moved my cordless phone to another room, powered off my external USB drive, powered off my iPhone... the cursor still seemed possessed.
Then I turned off Airport. Bingo!

Well... maybe not. If I move too fast, I lose control of the cursor again. There seems to be a lag.

Nice try, Apple.
I'm returning it to the store for a refund.

At least relief that I am not losing my mind here- my magic trackpad worked awesome for about 5 minutes then did the drunken pointer routine. Tried everything from turning off mouse to moving locations to playing with the bluetooth settings to removing the batteries. Definitely more than just interference from the magic mouse(tried that turned off and removed from the room.) HELP apple- fix this amazing device!

Spare a thought for me...

I am using BT keyboard and TP on my MacBook, which is right next to my old iMac, which I simply cannot get the TP to work properly on. I also have the iPhone (with BT off) and my BT Magic Mouse for the iMac on the desk. I also have WiFi router next to my MacBook.

I find the TP works great, but every now and then I also get the erratic movement problem. It goes away after a few seconds.

After reading this thread and based on my previous problems with BT devices on the MacBook I am convinced it is interference with the WiFi router that causes this.

How do we fix it?

Do you use time machine? My symptoms are exact, except 100% of the time the trackpad goes wonky, I look up and I am in a backup. Since I backup wirelessly, it is possible it is wifi as well since this is probably the only time during the day that my connection is stressed.

No, I don't use Time Machine, but I do have both Macs connecting to the router wirelessly. Next time it happens I am going to make a point in checking to see if the iMac is maybe downloading something.

What's really weird about this MT is that it works 100% on the MacBook, but when I try it on the iMac it freezes up if I touch it with 3 or more fingers. So today I bought a new Bluetooth dongle, put it on the underside of my iMac keyboard and it began working perfectly. Yay! for about 5 minutes because as soon as I connected up the BT Mighty Mouse to the MacBook it started the 3 finger freeze again. Reverse the installations and everything is fine again, barring the occasional erratic tracking of the MT.

I have all the updates installed on both machines. Weeeeeird.