My 12 month old Shar Pei just won't come back when let off lead, I could be waving a freshly cooked pork chop and she is just not interested!! Have tried squeaky toys - no! Slight interest in a dog whistle, I don't think her hearing is great. I don't let her off lead now, I feel terrible and desperately want her to play, but I just can't risk her not coming back when I usually have a 4 year old in tow!! Any advice, anyone??