Support for the iSAC audio codec will be removed from Chrome in milestone M110, and the code in WebRTC will be removed in the corresponding WebRTC branch.
The Opus codec has been the default and mandatory-to-implement full-band audio codec for WebRTC for many years. Meanwhile, iSAC makes up no more than 0.01% of the WebRTC audio traffic in Chrome, it is not widely supported, and the cost of maintaining and keeping the code secure is hard to justify.
We suggest that any current users of iSAC should migrate their applications to Opus, which is a full-band codec with superior audio quality. Alternatively, the G.722 codec is still available in Chrome as a low-complexity wideband option.
The WebRTC team