The most annoying voicemail you could ever receive is one where the caller speaks so quickly you can’t understand what they’re saying. At that point you end up having to call them back anyway just to figure out what they wanted. If you thought it was bad for you, think of how terrible it is for the older generations who have a hard time hearing as is.
If your grandparents struggle with hearing, then the Slow Playback Answering Machine Telephone should be a proper aide. It will not only increase the volume, but will also decrease the speed at which the message is played back. The buttons on the face of this phone are huge, backlit, and there is a large light that will go off any time the phone rings. There are also speed dial buttons, a built-in phone book, and it is compatible with hearing aids. This is a $170 phone that will make sure the message definitely gets through.