Same! I very occasionally find bits in my mouth (repulsive), but I only realised it was the cause of bad breath like a year or less ago. I was at my wits' end having given up smoking and taken oral hygiene to the max (my nightly routine is no less than twenty full minutes) yet STILL the stink went on. I watched some youtube video of a guy taking out his stones with a Q-tip and thought "there's no way mine are so big; mine are small" - not realising that the ones I find in my mouth are merely smaller broken-off bits of a much larger whole (bleugh!).

Took my phone's torch and a mirror and saw the fuckers; removed gently with a Q-tip and couldn't believe the size of the things! Pure white-ish yellow and all rancid. Demonic throat oysters. The warm salt-water REALLY helps though; it kills the bacteria that makes them grow, and rinses out the particles that are responsible for them in the first place. Alcohol or other mouthwash will only make it worse.