Mandarin question

[jacknjill]

I just got a few pair of young Mandarin, (2010 Hatch), and they are in the process of pairing up now. I noticed an occasional sharp chirping sound from a hen, almost like a cough / sneeze. I haven't noticed that before. Wondering if that fits in with their rutuals or if it is respiratory. Always paranoid when I bring something new home.
Thanks