There was a report from China's first manned mission of a sound like "knocking an iron bucket with a wooden hammer", which was eventually determined to be air pressure changes[0].<p>But the fact that this sound is coming through the speaker, and the way it restarts around 1:10 (unless that's just a comms hiccup), makes this seem like some kind of electronics issue. Sounds a bit like an alarm/warning, even.<p>[0]: <a href="https://usa.chinadaily.com.cn/china/2016-12/02/content_27545348.htm" rel="nofollow">https://usa.chinadaily.com.cn/china/2016-12/02/content_27545...</a>