I will try the experiements suggested and figure this out! It damn well better not be the jack!
For newer phones getting the jack fixed is not that expensive. For older types of Samsung phones it can be more expensive than getting a new phone
My phone is a Samsung Galaxy S3. That's probably considered a dinosaur, right?
The last Samsung the boy had was flaky. If he discharged it to the point of it being completely dead, the only way we could get it to charge was through the USB port on the computer it would only finally start to charge after about 10 min of sitting there. Once it got a 1/4 of the way there you could plug it in the wall to finish charging.
Once completely dead it would just remain dead if you plugged it into the wall...it would not start to charge even if you left it plugged in overnight.
I have the same phone as CBC and a battery optimizer app that took the phone from running out of charge in a day to lasting two or three days. Of course, like most Aspers, I don't use the phone for calls, just texts to Py and the doctor and for directions or to check a QR code. Mine does wait a bit before registering if the battery has run out but since I usually plug it in to the computer I don't know about that. I have an extra battery plus a fully charged one in my US phone so if I run out of battery I just change it.
I have a gazillion plugs because all but one of my devices are samsungs (the post on how many belongs in the developed country thread) and have the same chargers. No clue how much they cost. the chargers generally don't cost more than $5 from what I've seen. I've never had a charging socket fail, but guessing it's because I don't use them very much. Some are not even out of the boxes.
I won't be giving up my S3 until it isn't supported anymore. New isn't always good.