My GSD has been shaking his ear and whines when doing so, i've had him to the vets and they can see no sign of infection, (smell or discharge) nor can i but it's obvious he's in pain.
The vet suggested he may be allergic to something? and said to change his diet to Hills science? I declined as he has been a fussy eater and i know it maybe frowned upon but i have got him to eat pedigree chum and he gained a bit of weight so i'm a little bit concerned to take him off it to something he will not eat and so lose weight again.

I was wondering if anyone had encountered similar symptoms?

He's 8yrs old long haired and shakes his head at least once an hour not constant though.

Did the vet check his teeth?

my nellie got into the habit of shaking her head