They may have taken head off in a troubleshooting effort ,maybe, and didnt retorque it correctly. Id take it off, look at the ceramics and such, wipe some Vaseline(just a little) on the ceramics and put back, retorque it to spec and check it out.
What I sorta get a kick out of, is how many machine builders totally miss the point of an unloader block.
Correct use of an unloader block:
I’m planning on getting a new unloaded for it. So I should just mount it directing into the block and run the short piece of hose direct into the pressure side of the pump ?
You might find using JIC swivel connectors (if you can source them) between the unloader and block will facilitate changing it out when it eventually fails.