Wake up via timer, but wake up source says via EXT (interrupt)

[zjustin]

Hi Gurus

I encounter something really strange,

my device (ESP32) goes deep sleep and wake up at fix interval, it can also be wake up via a button press.

My code has been working well, but recently I encounter a very strange problem with a new battery (trying to test a 2nd source battery).

the problem is when the battery voltage drop to close to 3.3V, my ESP wake up source start telling me , the wake up is due to button press instead of wake up timer. but the time stamp clearly shows it is woke up at the exact timer wake up time, and no one is pressing the button. This behaviour does not happen at all when battery voltage is high.

any one seen such issue before ?

thanks in advance