My Xbox Controller Disconnects Every Few Minutes And Reconnects On Its Own

The regularity is the useful detail here. Interference and range problems are irregular, because the thing causing them comes and goes: a microwave, someone walking through the path, another radio on the same channel. A drop every three or four minutes that recovers in about two seconds is a repeating internal event, and there are two common causes.

The first and most likely is controller firmware. Microsoft have shipped several updates specifically to address periodic disconnects, and a controller a year and a half old that has never been updated is very likely behind. Updates are not automatic unless you connect it to a console or run the Xbox Accessories app, so plenty of controllers are running their factory firmware. The onset a month ago with no change at your end fits this too, because a console system update can change the wireless stack underneath an old controller firmware.

The second is a battery contact that has lost tension. The springs in the AA compartment weaken over time, and a momentary loss of contact drops the controller instantly, after which it powers back up and re-establishes the link in about two seconds. That matches your timing precisely. Fresh batteries do not help, because the problem is the contact rather than the charge. A quick test: while the controller is on, press the battery door firmly and gently flex the controller. If you can provoke a drop, the contacts are your answer.

One more thing worth knowing. Microsoft maintain a page about rolling firmware back, because a small number of controllers develop connection problems after an update rather than before. If updating makes it worse rather than better, that is the route, and it is a documented and supported path rather than a hack.