Here is mine - it works perfectly
echo -n 'ascset|0,setpool,root,root,stratum+tcp://btc.ss.poolin.com:443,btcpig.001,123' | socat -t 10 stdio tcp:192.168.2.'$count':4028,shut-none && echo
The only difference is the quotes?
Thanks for the reply! What version FW are you using? I get the same error.