New 5k imac. Filevault causes slow mouse and keyboard response during login

just got my new 27 inch 5k imac. 1 tb ssd 4,2 GHz i7 and radeon pro 580 gpu. I have the new wireless Apple keyboard with numbers (the large keyboard) snd the new magic trackpad which i ordered along with my brand new 5k iMac.

I have enabled filevault on my imac and it took about a day to encrypt the whole disk but that was expected.

What was not expected however was that the imac now sort of hangs during login. When i first move the mouse and start to type type in my account password after I reboot the computer it takes a few seconds before the keyboard and mouse responds even though the boot process has finished.

To explain better: I reboot, and when presented with the logon screen i move the mouse and type in password and this is when the mouse and keyboard is non responsive for a few seconds.

So when i type in my password the first few letters are not registered before the keyboard suddenly reponds. Extremely annoying!

When i turn filevault off everything is perfectly fine. Ive tried a complete reinstall of sierra osx and have also run the disk utility to search for disk errors but nothing helps.

I seriously consider returning my new imac because of this issue, but as i have no idea whether it is a hardware or software related issue i do not know if a replacement iMac will even fix the problem.

Anyone else with the new iMac having the same problem? Will a replacement iMac fix the issue for me?

 

Yes. It only occurs during login. very very annoying. you have to type in a few letters before the keyboard responds at all. same with the mouse.

 

Sounds plausible, but still VERY annoying. On my ild MacBook Air I do NOT have this issue at all, but that computer obviously does not have a bluetooth keyboard and mouse.

Can anyone in here confirm that they experience the same as I do with their FileVault encrypted 5k iMac?

--- Post Merged, Jun 25, 2017 ---

 

thank you very much for your information. I guess there is no point retune my iMac at this point, as a new one most likely will have the same issue. Very very disappointing and not very "Mac-like" with regards to user friendliness. Extremely dissapointing, as I will most likely end up running my imac unencrypted.

But for the sake of getting a 100 per cent confirmation - anyone in here with a brand new 27 inch Imac who have the same issue?

 

Can anyone with a 2017 imac confirm that filevault causes this lag on keyboard and mouse upon entering logon credentials?