Hello Diego,
welcome to the Polycom Community.
The IP330 was no longer sold after 12/31/2009 and the support for the IP 330 ended back in 12/31/2014
Newer phones support the tcpIpApp.keepalive.tcp.noResponseTransmitInterval parameter but your old SPIP 330 does not.
Maybe time to invest in some currently supported phones as these phones are at least 8 or more years old.
Best Regards
Steffen Baier
Polycom Global Services