OMG..i was sure i answered...i must be going nuts:P
Well, i would recomend you buy a cleaning solution specially made for dogs, you can do so at at pet store or even at some supermarkets that have a pet product section...I am not sure if the alcohol would irritate the skin. Also the cleaner reaches deeper inside the ar canal making sure it is always clean.
I clean Mojo's ears after every bath (usually every 7 to 10 days) and there is hardly ever any wax...so if there is excessive wax and residue check with you vet, it could be a little infection, it is always good to be on the safe side
Hope it helped!