Every agency has a number in their head for what a video actually costs to produce. Very few include the hours lost to audio-related revisions, and that's the number quietly eating your margin.
A video editor handling picture, color, and audio is doing three jobs, and audio is usually the one they're least trained for. That shows up as rework: a client flags that the host sounds muffled, the editor reopens the timeline, adjusts EQ by ear, re-renders, re-uploads, waits for approval again. Rework is one of the most underreported drains on creative agency profitability, and audio fixes are exactly the kind of rework that never gets attributed to the actual cause: a generalist doing a specialist's job.
It's not that your editors are bad at their jobs. It's that audio mixing is a specialist skill, and most video editors picked up just enough to get by, not enough to catch problems before delivery. So the client becomes your QA department. That's an expensive way to find out your audio needs work, because every round of "can you fix this" costs you time you already billed for and didn't budget for.
Start tracking revision requests by category for one month. If audio-related fixes show up more than once or twice, you've got data, not a guess. At that point, the math is simple: paying a flat rate for a dedicated audio pass on every video is almost always cheaper than absorbing the editor hours spent on audio-driven revisions, because you're paying for it exactly once instead of paying for the mistake and then paying again to fix it.
Riot Anthem Studios handles audio post for video agencies as a fixed, predictable line item. One pass, mixed right the first time, delivered ready for client review. No surprise revision rounds because the mix wasn't dialed in before it left your hands.
Every hour your editor spends fixing audio after the fact is an hour you're not billing for and a client interaction you didn't need to have. Audio revisions aren't a cost of doing business. They're a cost of not having someone dedicated to audio in the first place.