Same problem here: I'm leaving the monitor ON or OFF for several hours and then the touch controls stop responding. Yes, this happens even if the monitor is powered ON. To be able to turn it OFF, I'm unplugging it, leave it like that for 20-30s, plug it in again, it automatically gets powered ON and then the controls start working again and I can turn it OFF.

Does anybody know how to fix this issue?

My videocard is: Gainward GTX760 (looks like nVidia reference design) connected to the monitor using an HDMI cable.

Same problem! I bought 2 screens. Only 1 has the problem the other doens't. Very annoying

Get those monitors exchanged.

* Go back to the top of this Monitor Forum
* Open "FAQ Monitor"
* Open "Monitor warranties and instructions"

the problem is, we have 4 of them here and they ALL do this. there's nothing wrong with them otherwise and exchanging them just to get the same "results" would be a big hassle. 

There will not be any in home hot fix or anything like this. Exchange one of them and see if the replacement has the same serial and revision, and does it have the same issue.

I have the same problem. I bought this monitor a few days ago and the problem is that after a couple of hours of operation the touch buttons do not respond. I can not turn off or turn on the monitor. Menu buttons also do not respond to touch. I must remove the power cord and reconnect it for buttons to work again. I will replace it.

I have exchanged mine, REV A00 from June 2014, for another one from June 2014 with a different revision, A01. Unfortunately the problem still shows up. At the office we have 4 more, but I only had time to test a single one and the end result is the same. That one is A00 from December 2013.

Any suggestions?

Probably more people would complain if they'd turn on/off their monitor instead of leaving it in standby mode.

I can only speak to the Americas stock. Here, the U2414H A01 released on May 18, 2014 corrected the button issue. But you mentioned your A01 from June 2014 still has the issue. All you can do is keep getting exchanges.

I tried to email the local RMA service again about the issue but it seems that my personal email address has been added to their blacklist. Probably they didn't like that I questioned the fact that the monitor I received from RMA didn't look like it was a new one. That's because the monitor didn't come sealed in a retail box, neither packed in something that made it look like it was brand new. They just replied that they used the monitor to test the issue, and then it seems I got my email on their blacklist:

Delivery to the following recipient failed permanently:
     dell.rma@lasting.ro

Technical details of permanent failure:

I have never heard of us blacklisting an email address.