Why does Skype periodically play a file download cancel sound?

Question

Skype

Skype is running around the clock. The last weeks, every day 1-3 times I hear the sound of a file download error (or the start of download, just now I’m wondering what kind of sound). No notifications pop up.
I have more than a hundred contacts in Skype, from time to time I connected to various conferences (chat) in which there were usually about a dozen people and this was not the case, but recently I connected three conferences and in one of them someone uploaded a file, there must have been some kind of error at him (I did not accept this file, there was not even a cancel button, if I understand the reason correctly).
I don’t want to disconnect from conferences yet, especially without knowing exactly which one creates the problem. Is there any way to find out exactly where this erroneous submission occurs. Any log?
I also can’t turn off the sounds of notifications for working with files, because occasionally this functionality is required.

Answer 1

I have the same (Mac OS)

Answer 2

I have Skype for Mac OS, it was cured by unchecking "Play audio signals related to the subscriber's network status"