My lab did the same thing I took it to the vet, it was ear mites the vet gave me a wash and drops to use twice a day, it was a bit tricky trying to put the drops in and when I got them in I had to hold the dogs head as he would shake his head and the liquid would pour out, hes fine now mite free and happy.
I have a black lab and he has chronic ear problems from the time he was a pup .do the smell realy bad? My vet gave me 2 kind of ointment one is animax the other is dermalone I clean them realy good then squeeze in the meds I treat his ears once every 2 wks I have been doing this for 11 yrs if not we both are going crazy it could also be food allegy good luck
Most likely an infection or mites as fleas don't usually cause this problem. Take him to the vet.
My black lab had sugary for a hemi toma not spelled right about 2 months ago her ear is not swollen like it was but she still shakes her head what can I do for her without the expense of having another sugary
Possibly earmites or ear infection. Do his [inside] ears smell foul? If so, then I would presume it is clearly not fleas...♥Nassy