chroot'd sftp fails with "connection closed"

[jerrac]

First, I did find both of these knowledge base articles:
https://kb.plesk.com/en/8602
https://kb.plesk.com/en/114756

My /var/www/vhost/chroot has the sftp and lib files in them. As do my site directories.

Filezilla says "Could not connect to server".

auth.log looks something like when I sftp from the command line:

Mar  8 13:04:56 pleskhost sshd[516]: Accepted password for davidtestalpha from 10.152.2.100 port 63289 ssh2
Mar  8 13:04:56 pleskhost sshd[516]: pam_unix(sshd:session): session opened for user davidtestalpha by (uid=0)
Mar  8 13:04:56 pleskhost sshd[532]: subsystem request for sftp by user davidtestalpha
Mar  8 13:04:56 pleskhost sshd[532]: Received disconnect from 10.152.2.100: 11: disconnected by user
Mar  8 13:04:56 pleskhost sshd[516]: pam_unix(sshd:session): session closed for user davidtestalpha
Mar  8 13:05:01 pleskhost CRON[534]: pam_unix(cron:session): session opened for user root by (uid=0)
Mar  8 13:05:01 pleskhost CRON[534]: pam_unix(cron:session): session closed for user root

sftp works just fine if the user is not chroot'd.

I double checked the my test account's directories matched: http://docs.plesk.com/en-US/12.5/ad...structure/virtual-host-structure-linux.68806/

Server info:
OS ‪Ubuntu 12.04.5 LTS‬
Plesk version 12.5.30 Update #24, last updated at Mar 3, 2016 01:26 AM

I have had this problem for years, since before I upgraded to 12.5, I just haven't had time to really dig into it.

My previous version was 11.5.

Any ideas?