Free plans display a SoundToggle badge on players and portfolio pages. On paid plans (Pro, Studio, Enterprise) the badge is removed by default.
The badge is also how players earn referral credit. It carries your personal referral code, and its text matches the player it appears on ("Create your own before/after player" on an A/B player, and so on). When someone clicks it, signs up, and later pays, you earn credit — see the Refer & Earn articles for rates and details.
Paid plans can opt back in from the Refer & Earn page ("Show badge & earn on my players") to keep earning from their players. The badge never appears during a trial, and turning it on is always your choice — downgrading to Free re-enables it automatically.