Any reason to chinchilla barking?

my chinchilla was barking at around 7am this morning. i read that it's cuz he isn't adjusted to change... but i've had him for four weeks, and this is the first time something like this has happened. he did just get a new cage on thursday but i feel he's adjusted quite well to this one as it gives him more room to play. i let him out nightly, feed him and change his water of course, give him LOTS of attn, give him a dust bath. any ideas??