[Motorola Droid 4] Sjaakbanaan:
Since the last few days I've been getting some strange issues with my touchscreen. Sometimes parts of the screen (or the full screen) do not respond, and even the softbuttons are affected. When I take the phone out of my pocket, it either responds normally (I use pattern lock) or tries to use the emergency dialer or emergency contacts, and sometimes even tries to call a number from the emergency dialer (number 2 and luckily not 112..)

When in the launcher, it sometimes opens an app (like my calendar) and slowly scrolls either sideways or vertically. Turning the screen off and on again once or twice usually solves it for a (short) while.

I've already read some threads about it and ruled out the following causes:

The phone is not connected to any charger when this happens.

It still happens after cleaning the screen (just with a cloth, no liquids)

It still happens after disabling CPU Tuner. I didn't overlock the system, but used some custom power settings and different governors which apparently can also affect this behaviour.

The battery is still original since nowadays I prefer to use external chargers instead of buying a big battery for every new phone

The only things that changed recently are:

I installed the OwnCloud app, but that doesn't seem related.

We moved to another office building, in which the carpet generates more static electricity.

I gained some weight which may put a bit more pressure in my pant pockets than before :P

It started happening a few days ago, after using the .215 ICS leak for a few weeks without issue. I seem to get the problem less at home than I do at work, which makes me think it's either the static electricity or CPU governor (since battery percentage is lower by the time I get home again, so it might use a different governor). However, I've been using CPU Tuner for quite some time before this issue started, and the issue persists after disabling it.

So I am guessing it's any of the following causes:

Static electricity

Keeping the phone in my pant pockets which may put some pressure on the screen

A problem with the battery or screen somehow (moisture?)

Some other hardware issue

Some software issue

Does anybody have any tips or other ideas about this? Thanks in advance.

Edit: I enabled some development options to show touch pointer location (white dot) and trails. Screenshot added. Phantom touches seem to be focused in the bottom center part of the phone, which is probably around where I grap it when I take it out of my pocket. Trails usually disappear the next time you touch the screen, but in this case the trails kept growing / adding. I made some real swipes (upper half of the screen) and they 'stuck' without the phone responding to them (the application did not scroll) due to the parallel phantom touches in the bottom. In this case the phantom touches blocked my real input, in other cases they cause some behaviour (scrolling etc.). However, sometimes when the screen is not responding, there are no phantom touches visible in this display mode.

Edit 2:The no-touch input problem seems to be 'triggered' most of the time I open the keyboard. Sometimes this is followed by the phantom touches, but usually they start occuring in the portrait mode lock screen.