Sony devices cannot connect after server reboot

Hello.

I'm using Serviio for a long time (2011) and I'm in trouble since 3 months with my 2 Sony devices (KDL-46EX500 tv and BDP-S3100 bluray) which can't connect to my Serviio computer (Ubuntu 14.04 LTS + Serviio 1.5.2) after each time I reboot it. Others devices (Windows 8.1, Android 4.2.2 + BubleUPnP 2.5.4) can, but not my Sony ones.

To solve temporary the problem, the only way is to delete my tv and bluray renderer profiles and to stop and start the server from the console. It works until the next Serviio computer reboot.

Do you have an idea of the cause of the incident and how to solve it ?

Thanks for your help.