I'm using an iPad 2 with 32 GB and SIM-Card-Slot. The sim-card-slot is not in use, so it's empty. Installed is the latest iOS version (no updates available). I don't use any jailbreak (and didn't used it before). All my apps are installed out of the App Store, so it isn't a development device. There is no "pseudo-background-app" like a anti-virus-scan tool or something like this. The free space is round about 2,5 GB.
Since some weeks ago the iPad is crashing at several usages. I hear music streaming, after some songs it crashes. I write an eMail it crashes after x minutes. I use an app and it crashes after y minutes. The time is always different - sometimes it runs for 2 hours - sometimes it crashes after 2 minutes. If I hear music it crashes in "standby" / "background".
It does not depend on the energy. The effect is the same if it's loading at this moment or it has 100% or 15%.
A crash starts by a freeze. Nothing works, after 1-2 minutes the freeze changes to black background and an dark-grey apple. Then the apple changes to the "standard"-colored (brighter) apple. After some minutes the iPad has restarted. But this is no guarantee that it runs now without a new crash.
Hope anyone has an idea to solve this problem.