I can empathise with you here, my last phone (read: palmhusk) got to a point where the back of its shell was coming off, and the volume button would fall inside the phone, so I'd have to push a needle or paperclip between my phone and its casing (of the phone/palmhusk itself, not like a phone case) and pry the volume button back out. Really fucking annoying. Maybe look for headphones with a volume wheel?