Network printer blocked randomly when printing

Dear support,

i am posting here because i am lacking of idea regarding a network printer problem that worries users and manager and it makes me crazy as well..

This problem appeared one month ago suddently without network or system change in my domain. Im using Window Server 2008 R2 Standard edition

When my users are sending files to any printers, it suddently block all of them without the possibility of removing files in Queue. When im looking at spooler service, eveything goes right, i can restart the service but the problem still persist, my only way is restarting the server which is also file server.. I tried everything, updating drivers, reinstalling printers on the server, deploying by GPO, nothing fixed my issue. The problem occurs mainly when large files(over 50 Mo) are sent to the printers but this can happen with small files <1Mo. I already checked if this can be a problem for the printers with provider and they answer me to do some test in local with USB Key and there is no problem. I don't know how to troubleshoot this and i would be extremely grateful for the help on this.