Every so often, I pick up the phone to dial out and get a fast busy tone. I hang up, wait a few seconds, and try again, and I have dial tone and can dial out.
I have not noticed any pattern or timeframes when this occurs.
When looking at my online call log, I see calls at very random and arbitrary times of the day in the Outgoing column from my own number and TO the same number. ALWAYS after that there is an entry that the call went to voice mail. There is never an actual voice mail message, of course; I guess it hangs up before VM detects a valid message.
There appears to be an entry like this every single day, but, again, at very different times and with no discernible pattern.
Why is my own phone number trying to dial out to itself and at various times of day and night?