Cat seems to behaving a swallowing problem and sneezing?

I recently took my cat to the vet as he was losing weight in his rear 3/4 by his rear haunches. He is otherwise healthy, he eats and drinks with no issues, uses the bathroom with no issues. Well the vet tested his urine, blood, and fecal said his kidney's, liver and  thyroid are all in shape in relation to his age which is nearly 12. Only issue was a heart murmur which we need to do some more testing on coming up. Something he has done lately that I forgot to mention to the vet is swallowing frequently and making gulp sound. Today he followed that by sneezing. I feed him Blue Buffalo food and he always has fresh clean water and wet cat food with water 1X per day as well. Any idea what could be causing the swallowing issue? Anyone can offer feedback? As he gets older I worry more, hes my buddy and I want to do the best for him. Thanks.

Bump, Anyone's cat having a similar issue with trouble swallowing in the past that could shed some insight? Thanks.

The gulping makes me wonder if there's an issue in his mouth, either with his teeth or gums. Did the vet do a thorough check of his mouth? Is he drooling at all? Sometimes, full mouth x-rays are needed to diagnose a mouth issue.

If the sneezing was a one-time deal, then I wouldn't worry too much, but if it continues, it could be from any number of things. Allergies, URI, etc.

It could be that he's got drainage going on and that gulping is what is referred to as overexaggerated swallowing.  How long have you been feeding him Blue Buffalo and did this swallowing start before or after you switched?  I have a cat who is allergic to BB and it exhibits with this type of behavior and coughing.