A. Raspy breathing is very difficult to hear over the internet, so it's kind of impossible to say for sure, but let me give you a very simple, very practical guideline.
The activities of the newborn infant include eating, sleeping, poo-ing, pee-ing and, most importantly, growing. All sarcasm aside, if your child is able to achieve these goals, especially if you note that his growth follows the expected pattern, you can be relatively sure that nothing serious is wrong with him medically.
Of course there are a whole host of diagnosis to consider based on the history you have supplied, including asthma, nasal polyps, deviated septum, laryngomalacia (kind of a laxness of the muscles in the larynx leading to funny sounds when the baby breathes in), etc. But if your baby is doing all the things he is supposed to be doing, and achieving all his developmental goals on time (he sits by now?), you can be relatively sure its nothing too serious. Waiting until he is older will allow him to outgrow certain ailments (laryngomalacia), grow into others (asthma) and be properly investigated should it become necessary in the future. At that time he'll be easier to investigate and better able to tolerate such investigation.
Without hearing your son myself, that's the best advice I can give you.
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