When I take my blood pressure manually, I sometimes hear a pulse beat just as I start to deflate the cuff. This then makes it hard to hear where the systolic pressure starts. This doesn't happen all the time though, so I am wondering what this is.

That's one of the reasons that manual is a misery. THe "did I HEAR that" syndrome is all pervasive...even DOCTORS can hear what they want to hear perchance.

So I guess the automatic method is better? Is the automatic method more accurate as well?

It's easier and accurate enough.

When I take my blood pressure manually, I sometimes hear a pulse beat just as I start to deflate the cuff. This then makes it hard to hear where the systolic pressure starts. This doesn't happen all the time though, so I am wondering what this is.

You might not be pumping the pressure high enough.

Taking one's own BP manually is not that easy. For instance, before you hear the first solid pulse (Systolic), there might be some lesser sounds, or clicks, which also count towards finding an accurate Systolic reading.

An accurate automatic digital BP machine is the way to go, for me. They are made to interpret the pulse sounds correctly.