FTP is very slow in release 3.5

[dimag0g]

I have a vsftpd server on Debian (plain FTP, not secure) which works fine with FileZilla FTP client, and also worked fine with the old pplay 2.1. However, the old pplay won't work with the latest FW, so I had to switch to the latest release, 3.5. It technically works, but is painfully slow, taking several minutes before a movie playback starts.

I collected a log corresponding to opening a single movie in pplay 3.5. It features several 426 connection errors, and the actual time is wasted when the connection is restarted right after:

Fri Jan 7 13:40:11 2022 [pid 25723] [user] FTP command: Client "::ffff:192.168.0.12", "RETR /home/user/video/MOVIES/test.avi"
Fri Jan 7 13:40:11 2022 [pid 25723] [user] FTP response: Client "::ffff:192.168.0.12", "150 Opening BINARY mode data connection for /home/user/video/MOVIES/test.avi (1572769792 bytes)."
Fri Jan 7 13:40:11 2022 [pid 25723] [user] FTP response: Client "::ffff:192.168.0.12", "426 Failure writing network stream."
Fri Jan 7 13:40:11 2022 [pid 25723] [user] FTP response: Client "::ffff:192.168.0.12", "229 Entering Extended Passive Mode (|||57663|)"
Fri Jan 7 13:40:34 2022 [pid 25723] [user] FTP command: Client "::ffff:192.168.0.12", "REST 10252"

This pattern repeats several times until the download goes through and the playback finally starts.

I observe the same behavior when I use ftpd instead of vsftpd