strange sound from transmission box?

[yuwa]

when my car is cold, theres only a little sound when i shift to D, R or shift back to N, and when the car is totally warm, oil temp to mid, i can hear that clearly in the car with window closed. the sound is like the gear is hard to get in. also, 3rd gear to 2nd gear and 1st gear is not smooth. i feel like the there a brake during down shift. anyone can tell me why?

this was taken from outside, you can hear the sound after 30sec

the 2nd one was taken from inside, the sound in person is much more clear. but still can hear it from the video if you listen carefully.

can anyone tell me whats wrong with my car?