Q: Bluetooth Apple Magic Mouse jumps and moves erraticlly on screen

Sorry, I forgot to mention - the one action I thought the jumping might be related to is resting my left hand on the top of the computer, below the command key. That seems to make the jumping problem worse. Has anyone else noticed this? If so, it will be a hard habit to break!

I just had this happen to me also. This was the second time I have encountered the problem and the remedy for me was to logout and log back in which may the problem disappear. This time as I was logging out one of the applications required me to dismiss it before it would continue. I noticed at this time that the mouse had restored back to its normal operation. This implies to me, there is something in one of my applications or a background task causing the problem. I will try to track it down The next time it happens.

I had this problem recently occur every few minutes, both using a Magic Mouse and with BT off using the trackpad on a 13" aluminum MacBook.

I reset the PRAM yesterday, and the issue has not resurfaced.

--Mike

I've had the erratic cursos-moves at home and at the office, with a number of different magic mice, bluetooth-keyboard connected or not, usb-devices connected or not, miniDisplayport-adapter connected or not. only thing that helped was turning off airport. has been a reliable fix, but entails certain disadvantages like not having wifi. had a spare aiport-express which i use as a wifi-ethernet-bridge, but this seems ungainly.
and: other people at the office have the same problem and use the same solution.
andrei

Same exact thing for me, thanks for the suggestion! Everything works fine now.

I'm having the exact same problems with the jumping mouse issue. I've tried three different mice. One wireless and I get the same results from all of them. Erratic jumping which is extremely irritating. I've only had my hexacore for a week and it's always performed that way. Dropped the airport and no difference. The only thing that works is getting rid of my second monitor. One is dvi and the other is thru the mini display port. Both monitors 'cause the jumping mouse but when only one of the two is plugged in the mouse is stable. I need a fix for this 'cause I'm an editor and need all the real estate I can get. Anyone know if anything is coming down the pipeline for a fix on this??

thanks

Just thought I'd chime in as well so there are additional cases for Apple to use IF they need additional data to try to remedy this issue.

I have both the Magic Mouse and the Magic Trackpad. Once this issue started, I disconnected the Trackpad, and the problem continued.

I don't think it's the Mini Display Port (MDP), because this started prior to connecting that.

I have all the USB ports full––two external HDs, Apple extended keyboard, and a Belkin hub. I tried disconnecting the hub, to no avail, and then the MDP to no avail.

Tried sans mousepad, to no avail.

I do web development, graphic design, and video editing, and this is a MAJOR issue for accuracy.

I'm using a 1 month old iMac.

Oops. I misspoke. I hadn't yet unplugged the MDP from my computer--despite the fact that the issue started prior to using the MDP. Since I unplugged the MDP, moments ago, the problem has ceased.

Of course, this is still a problem, because despite the awesome real estate of a 27" iMac screen, when doing video editing work, I use the second monitor's real estate in its entirety. Ugh.

cameron.purdy you are absolutely right,
it's a appears to pull it's power from the USB bus, here is what happened with me:
the problem starts last week, when I plugged in Samsung 23 LED & at the same time trying to copy large files from my Kingmax flash memory, the mouse goes crazy :S
Stop the copying files no need to disconnect the flash ( it returns normal )
keep copying & unplug the external 23 monitor ( it return normal )
although I am running ( 10.6.4 ) I hope they fix this usb bus soon on ( 10.6.5 )

I just watched a similar thing happen and I am on 10.6.5... So no they have not fixed it yet. I was just looking through some items on Amazon with a smooth mouse, then I heard my external USB drive fire up I assume due to Time Machine. The next time I touched the mouse it was just going crazy jumping all over the screen with the slightest moves. I waited until the external drive shutdown and imagine that the mouse movement was smooth again. I really hope they figure out a way to solve this. It is extremely frustrating to not have the accuracy that I should. As I am typing this, it is happening again. Come on Apple it is time to fix or recall this thing!

This has been an ongoing issue now for almost three years.

Check out the following links:

http://www.youtube.com/watch?v=OBzisliiVpg

http://www.youtube.com/watch?v=cR7Kht37Eig&feature=related

http://www.youtube.com/watch?v=NxLY3-pH-rs

http://www.youtube.com/watch?v=uTJ7Fq3SRlI

http://dae.cyberic.eu/blog/mouse-cursor-skipping-jumping-bug-on-mac-os-x/

First, I would file a report with

http://www.apple.com/feedback/magicmouse.html

Second, I would send Steve Jobs an email notifying him of the problem.

I had the same problem with mighty mouse going all over the screen on my brand new imac i7. After a while I realized that the problem began after I connected a second monitor to my computer. I unplugged the monitor and the mouse went back to acting normal again. This is a problem for me since I'm a video editor and use dual screens. I hope apple fixes this.

If you have more than one monitor, don't turn them off. If you do, the cursor gets confused.

Same for me: Erratic and Jumping Magic Mouse (pointer of course) since a few days.
After reading comments, disconnected 2 firewire Disks (self-power-plugged), an additional Display, and Spider3 probe (iMac-powered). turned off wireless-track-pad. Power off iMac, 5 minutes, then On.

Everything wend back to normal.

Try to reconnect peripherals one by one. Trackpad Ok at the moment.

yep its a second monitor problem... i was wondering why my magic mouse acted out constantly since a while now and remembered that this wasnt the case when i got the imac.
so i just cleaned up the mouse pad, tried out two other mouse pads, cleaned the mouse with a qtip, etc. while reading the threads here and as it turns out my second monitor was plugged in but not turned on. at the very moment i turned it on the jumping stopped...
i guess osx is confused by two screens and not be able to use the other. maybe some screen resolution stretching/unstretching for the mouse problem.