Have a vet double check for mites, though they're probably unlikely since you'd notice the dark build up they make.
Are his ears waxy at all? Have the vet check the wax for a yeast or bacterial infection, and check inside the ear to make sure there's no polyps growing - if there is a polyp it could cause hearing loss or there may even be a risk of it being malignant. So this isn't something to ignore.
The other possibility is allergies.
As for the sores, keep them clean, use ointment as you have been doing, and gently discourage Whisky from scratching. When he scratches push his feet down and tell him "no scratching". Eventually you should be able to get him to listen without you needing to actually stop him.
I would suggest that you rub at his ears to help with the itch, but until you're 100% there's nothing bad in them that isn't a good idea.
I have one who had terrible ear mites when I got him, they left a bit of damage. His right ear gets extra waxy. While he's been thoroughly checked out no one has figured out why that ear gets waxy - ironically my own ears do the same thing.
I keep his ear clean and when it itches, I tell him "no scratching" and rub it for him. It's prevented him from ever scratching his ears open.