My S20 5G has also been experiencing random restarts.
For context, I used Smart Switch to transfer data and downloaded the same apps as my old phone. Originally the random restart occurred when I was using the plug in AKG earphones that came in the box. But unfortunately, the restarts occurred even when the phone was running idle without any apps running in the background.
I then did the usual steps as recommended by Samsung after calling their support line: Switching the phone off and on manually, deleting apps, turning off Wi-Fi, wiping the cache portion and finally doing a factory reset.
After doing each of these steps, the phone still restarted. At that point the phone was sent for repair – but all that occurred was testing and a new software update. Unfortunately, after a day of use, the phone still restarted, and again I went through the usual steps e.g., factory reset.
Samsung then sent it in for repair a second time. I have just received it again, but this time, on the advice of my flatmate who works in IT suggested when turning the phone on, I do not download or transfer anything, turn the Wi-Fi off and simply leave the phone on without any apps running as if it were a brand-new phone. Having checked the Up time (under status), it has restarted randomly by itself AGAIN.
In their letter Samsung claim no faults could be found and that its possible that the restarts are being caused by rogue 3rd party apps or Wi-Fi connection, but having turned on the phone without downloading any third-party apps or transferring data, how is it not a hardware problem?
Anyone who has been through this, any help would be appreciated. Samsung are not offering a replacement as it has been longer than a month since purchase, yet the problem persists. Samsung’s response has been awful as they are just suggesting I send it in for repair again!