Sorry for the delay. It is a new problem. It used to work well for many years.
We had to work with our senior engineers to trouble shoot the problem. It turns out to be a compatibility issue with Chrome. Similar issues have been reported in other websites, e.g.:
Good News: We have fixed the problem over the weekend. It should be working fine now.
The problem is caused by Chrome's strange implementation in playing an .MP3 file: It sends a regular GET request to download the MP3 file. When the server starts sending the data, Chrome will immediately cancel the download. It then sends another GET request with range header to download the same file again.
Anyway, we have fixed the bug now. Please let us know if you still experience any problems.