This is an issue on OS7200 versions earlier then 4.11 (this is a pre-release version, the release version was 4.14).

It only happens on extensions on a DLI card in slot 1 on the main cabinet.

Upgrade to 4.14 or later.

I had todo this on a 2 cab running 2.63, so had to go 2.66, 2.69, 4.11 upgrading the lcp each time, and it was a old SM style MCP so it was slow.