by Yascher:
Read here, as Chuvacu as a fix for spontaneous speaker turn on during a call, advised to remove the latest updates of the Chrome browser.

by Yascher:
Today, Google, "what to do if when connecting to a PC the phone restarts". Well, I think, probably the static of something, you need to ground the USB in the computer or something else. It was not here:

"In the settings (Settings - Sound and Image - Call for Reminder) return the default sound to the system notification, or remove it at all."