When performing concurrent range requests, it seems that response headers get mixed which can cause requests to fail.

Here's a sequence of 5 requests for different mp3 files, where the first and the last request are selected. For all these requests, the Content-Range header is set to the Content-Length of the last request. This causes all requests where the Content-Length is smaller than the Content-Range to fail.

Note: If I perform the requests consecutively, i.e. wait for a request to be finished before performing the next one, everything works as expected.