A major problem I am having with gestures on 4 different iOS devices

Hi. I am having a problem with 4 different iOS devices and I am wondering if anyone can help me solve this problem. When I say devices, I mean all of them, as I use them all often and I also oftentimes use more then one of them at the same time. Before I describe this problem, I will give some background. I hope with the info I give someone will be able to help me figure out what is going on here. I have 3 iOS 8.1.2 devices: an iPhone 4s, an iPhone 6 and an iPod 5. I also have an iPhone 3GS running iOS 6.1.6. The iOS 8 devices are jailbroaken and the 3GS is not. They were all working just fine, then at the same time, they all started having the same problem. I have not updated the iOS or changed any settings on any of the devices so I can not even begin to guess what is causing the problem. What's even more strange is that I had 4 perfectly working devices, then they all started having this problem all at the same time. It does not happen all the time and the fixes I have found sometimes work and sometimes do not work. So the problem: I do a gesture and the device takes it as a completely different gesture. Some common ones are that I will try to do a 1 finger swipe right to flick from 1 item on the screen to another and nothing will happen, so I will preform the gesture again, and again and again. Then I just wait a bit, and the device stays silent for a bit, then very quickly does all the swipes all at once. Another thing that can happen is that I will do a 1 finger swipe right and the device will take it as a double tap and it will open something. Yet another thing is I will do a 1 finger double tap to open something and the device will think I did a 4 finger single tap near the bottom of the screen and will say bottom of screen. Another annoying thing is that I will do a double tap or swipe left or right and the device will take it as a 3 finger double tap and speech will go off forcing me to turn VoiceOver off and back on to get speech back on because once it goes off, when I do a 3 finger double tap to turn it back on, it does not come back on because the devices take it as a different gesture. And on and on. To make a long story short, every gesture I do, the device takes it as a different one. I thought maybe some dirt or something was on the screens and it was confusing the devices, so I took them all out of there cases and wiped the cases and the devices with a damp but not too wet cloth, then dried the devices and cases off and before I put the devices back in the cases I washed and dried my hands very good and tried using the devices again. The problem went away for a bit and my gestures worked correctly. So then I decided to leave the cases off. The devices worked good for a bit, then the problem came back. I washed my hands again but this time it did not help. So then I decided that if having the devices out of the cases was not going to help after all, I would just put the cases back on. I also oftentimes use my devices when they are plugged into a wall outlet charging. A few times I was using my devices and was experiencing the problem quite badly. I unplugged them and the problem instantly went away. I plugged the devices back in and the problem came right back. So then I started using the devices unplugged, but the problem came back after a bit even though I had not plugged the devices back in. So to make a long story short, sometimes removing the cases will temporarily make the problem go away and some times unplugging the devices will temporarily make the problem go away, but also, sometimes the devices will work fine when they are plugged in and the cases are on. Another thing that I have found that temporarily makes the problem go away is to turn the devices off and leave them for a long amount of time. Just turning them off and right back on does not work. They need to be left off for a while. I have not figured out exactly how long, but 5 minutes is too short and 1 hrs works. The problem seems to just come and go when it wants to, but sometimes removing the cases and or unplugging the chargers can temporarily make it go away, but it always comes back. Also, I turned off VoiceOver and got a sited person to try using the devices. They also experienced the problem. What is going on and what can I do to make this problem permanently go away? Thank you.