Sometimes when restarting xbsx makes a short weird sound

hi all
my logic is, besides the fan and disc player there are no other moving parts in the console. that said it worries me that there will be issues in the future which I’d love to prevent. the console is always very quite even after 4 hours or more of play. never noise from fan or disk, always very silent. occasionally though at restart this weird sound, it lasts a second only and sitting 3 meters from xbox I can clearly here it. the sound is not like a bip and not digital/electronic in nature but actually mechanical a bit muffeld. almost like a drag maybe a bit of friction. is something getting loose inside? I hope that someone had the same issue and can help to identify what if any part I’ll have to change in future. fan or drive ?? thank you in advance cheers AA