Playback of bird songs using speakers can be detrimental to birds and disturbing to birders. Use playback responsibly around birds and birders!

We know some birders may choose to use playback for attracting birds and we strongly warn against doing so when it may negatively impact birds (e.g., when birds are nesting, when birds are feeding young, when birds are otherwise stressed, in areas frequently visited by birders, etc.), where it is prohibited, and where other birders may overhear the playback.

Playback is addressed by the American Birding Association's "Principles Of Birding Ethics" with the following paragraphs:

To avoid stressing birds or exposing them to danger, exercise restraint and caution during observation, photography, sound recording, or filming.

Limit the use of recordings and other methods of attracting birds, and never use such methods in heavily birded areas, or for attracting any species that is Threatened, Endangered, or of Special Concern, or is rare in your local area.

Note that the ABA principles say "limit the use of recordings ... [for] attracting birds." Playback for attracting birds, if used at all, should be done judiciously.