During downloading, I get the following errors very often:
[mp4 @ 0000018137a6fb80] Application provided duration: 4446283915 /
timestamp: 4578421928 is out of range for mov/mp4 format
Furthermore I get two types of warnings:
1) [mp4 @ 0000018137a6fb80] "pts has no value"
2) [mp4 @ 0000018137a6fb80] Non-monotonous DTS in output stream 0:0;
previous: 8584539879, current: 29793240; changing to 8584539880. This may
result in incorrect timestamps in the output file.