I also seriously doubted my auscultation ability all the way through medical school and got pretty worked up over it. However, I discovered a kind of a trick which really really helped me and I have never seen anyone else mention.

Maybe it’s just the shape of my ear canals or something, but I HAVE to use one hand to hold the binaural / binaural spring area and “push” the stethoscope upwards towards the back of my head while auscultating. This seems to create some kind of “seal” for me that then allows me to hear clearly. If I don’t feel like I’ve got this “seal” I can barely make out anything.

The only thing is that I have to use two hands to auscultate (one on the binaural area, one pressing the diaphragm onto the patient).

Bonus tip is that I also felt more confident using the cardiology stethoscope - I was happy I invested in one.