Loud static and hissing for long duration from external intercom

Most of the time when I use ring to open to enter my complex it is fairly quiet on the external buzzer. Tonight when coming in it went crazy and was making some very loud and static hissing sounds for well over the 5 seconds which I’ve got it set to open for. Any idea what caused this as it would definitely be a problem with other residents if it continues to make those noises for the 30 plus seconds it went on for?

This has started happening again all of a sudden. Any reason for this?