Brief Answer:
Not concerning...

Detailed Answer:
Hi,

It is not uncommon to experience a bit of cough after a bout of cold flu. If the cough is not severe and there is no expectoration, I think you are alright. The crackling sound you hear is most likely a process of recovery and I will not be overly concerned here. It will resolve in a few days to a week.

You should consider drinking plenty of fluids and take benadryl syrup if the cough is affecting daily activities. Steam inhalation will also benefit you.

Hope this helps. Let me know if you need clarifications.

Regards

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