I'm trying to listen in to Beano this morning and all I can hear is myself

It sounds like my uterus is having a thunder storm or something. Everywhere is whirling or pulses

Anyway, I'm sure I can hear Beano underneath all of this noise but I have to hold the doppler right up to my ear and really concentrate on blocking out all the other noises.
Why is it somedays it's quiet in there and other days it's so loud I can't find a patch of my abdomen that isn't creating a noise? Does anyone else get this?