Selective watermarking of channels of multichannel audio

A method for selecting a subset of channels of (e.g., determined from) at least a segment of a multichannel audio program for watermarking and watermarking the selected subset of channels, and a system or device configured to implement any embodiment of the method, or including a buffer which stores at least one frame or other segment of a multichannel audio program generated by any embodiment of the method or steps thereof. Some embodiments generate watermarking metadata during program creation including by analyzing audio content to be included in segments of a multichannel program, determining at least one watermark suitability value for each channel of each of the segments, and including the watermark suitability values (or watermarking data determined therefrom) as metadata in the program. Some embodiments are implemented by a playback system which determines the selected subset of channels to be watermarked.