Re-locate the VHF antenna and try again. Try several spots that offer a clear view towards La Jolla. You've got a really big hill or mountain right in front of you and the signals coming around it are likely to be both very weak and very scattered. Just because a mounting location is convenient doesn't mean the signals are going to play nice and be there in adequate quality and power. You often have to go seeking them and that takes patience. My usual advice is "Don't drill any holes until you've verified satisfactory reception in that spot".
Here's what your signal path to channel 10 looks like:
Now you can see what you're up against.