Capture from DirectShow devices such as 4K60 Pro MK.2 or HD60 Pro may have a No Signal event after Valorant is launched.
Riot's anti-cheat engine Vanguard intentionally blocks this.
This does NOT affect UVC devices such as Cam Link, Cam Link 4K, HD60 S+, or HD60 X.
Riot has informed Elgato that DirectShow is a vector for inserting cheats into the game, which is why they outright block these devices, which is not limited to Elgato.
Riot is collecting feedback from affected users - Please get in touch with Riot support to leave your comments.