From Shih Tzu Daily:
Sarafina, the cute Shih Tzu lady hates fart noises, as her parent makes funny fart noises she gets shy and walks away . Once a lady always a lady!
Although this is not a noise phobia, if you Shih tzu shows any of the following signs you should defiantly talk to your
Trembling
involuntary urination
Hiding and escaping
Most incident of noise phobia start when the puppy is between 1 year to 2 years old and gets worst by time if left untreat