Strange keyboard and trackpad problems

[Everybodyknows]

My 2013 MBA has a weird problem:

The keyboard is almost unusable, either responding very slowly, not responding at all or producing uncontrollable strings of single characters. The trackpad has similar problems with the cursor only responding very intermittently, or more often not responding at all. An external USB mouse works fine thankfully, and with the on screen keyboard means it is just possible to troubleshoot. Another weird behaviour is the scroll function sometimes comes on locking one at the bottom of a page or list.

I have tried the SMC etc chip resets, reinstalled the OS and finally erased the disk and done a factory reinstal, but the problem remains. The problems even manifest in recovery mode, which surprised me.

What is really odd, is that these issues are not present on the initial log in screen, indicating that it is not a hardware issue! What I can't figure out is what is special about this login screen? I assumed it was a problem with the individual account, so only manifested once logged in, but as the problem persists in recovery mode that can't be so.

I have spent 14 hours working on this but found no solution. Most of my hair now pulled out, so... Any ideas?

 

[cerberusss]

if you create another account, does it happen there too?
Does it happen when it's running on battery, with the power adapter unconnected?

 

[bizzle]

My 2013 MBA has a weird problem:

The keyboard is almost unusable, either responding very slowly, not responding at all or producing uncontrollable strings of single characters. The trackpad has similar problems with the cursor only responding very intermittently, or more often not responding at all. An external USB mouse works fine thankfully, and with the on screen keyboard means it is just possible to troubleshoot. Another weird behaviour is the scroll function sometimes comes on locking one at the bottom of a page or list.

I have tried the SMC etc chip resets, reinstalled the OS and finally erased the disk and done a factory reinstal, but the problem remains. The problems even manifest in recovery mode, which surprised me.

What is really odd, is that these issues are not present on the initial log in screen, indicating that it is not a hardware issue! What I can't figure out is what is special about this login screen? I assumed it was a problem with the individual account, so only manifested once logged in, but as the problem persists in recovery mode that can't be so.

I have spent 14 hours working on this but found no solution. Most of my hair now pulled out, so... Any ideas?

FileVault login screen or regular login screen? Some keyboard/trackpad issues do not happen on the FileVault login screen because only basic drivers are loaded. The issues you describe sound like an issue with the IPD cable or the trackpad (which has the keyboard controllers in it).

 

[cerberusss]

I'd try a fresh install.

 

[Everybodyknows]

I did a fresh install, but the problem continued soon after setting it up again. it seemed to be associated with the particular user account, but I couldn't identify the app, data or whatever that was causing it. Took it back to the Apple Store, and WOW it worked perfectly!

Got back home and set up a time vault to keep it backed up. After 48 hrs it was locking up again and became barely usable. I used time machine to rewind to when it was working, but it remained disabled.

I was ready to give up and send it in for servicing when I came across this article: http://www.macissues.com/2015/05/14...quent-os-x-pauses-may-be-from-icloud-syncing/
This sounded like my problems, but mine was continual, not 'frequent' or 'intermittent', so I didn't hold out too much hope.

I turned off several of the iCloud services and POP it all started working again! Brilliant!

Problem solved!

 

[cerberusss]

Wow, that is a very unexpected solution... Amazing you found the article/solution yourself, and thanks for reporting back!