This episode was directed by Roxann Dawson, who played B'Elanna Torres in Star Trek: Voyager (1995).
Hoshi's handheld translating device is actually a General Radio sound level meter used to measure sound pressure levels in decibels.
The title of this episode, translated from Latin, is "Lone Voice".
Dialogue in Act Four between T'Pol and Hoshi is the first on-screen confirmation that T'Pol is Enterprise's first officer, in addition to science officer. This was frequently implied in previous episodes, with T'Pol asserting that her Vulcan sub-commander rank superseded Trip's Starfleet commander rank (Broken Bow, Part 1 (2001)), and with Archer consistently assigning command to T'Pol first when leaving the ship (and/or the bridge).
The Kreetassan captain is the twelfth character played by Vaughn Armstrong, including his recurring role as Admiral Maxwell Forrest. It is also the final new alien character he played, though said character later reappeared in A Night in Sickbay (2002).