Opus

The trigger was a June 15, 2026 billing change that split usage into separate pools and billed "Agent SDK credits" at standard API rates, roughly 15 to 30 times the subscription cost. Anthropic paused and rolled it back after the backlash.

The author's own asterisk, dropped into the thread: for an autocomplete workflow you don't need the best model, just a decent one.

The new encoder even ships a deliberate workaround: its author found FFmpeg's own AAC decoder mishandles stereo PNS, so the encoder compensates to keep playback correct.

It is constant-bitrate only and tuned for 48kHz, with 44.1kHz and 96kHz working but discouraged.

The catch skeptics keep raising: on the same benchmark, Opus beats every AAC encoder even at 64 kbps.