Connecting to a Source 1 Gameserver disallows usage of Sandbox mode.

[themertaza]

I was trying to idle on a Garry's Mod server in the background, but it makes me unable to use Sandbox mode, I had an issue where I was unable to go into Sandbox mode, then I rebooted my system, started Deadlock first, went into Sandbox mode first, then connected to said Gameserver, and was booted out of the Sandbox mode, and unable to go back in, port issue?