Certain aspects of the present disclosure provide techniques and apparatus for starting an extended idle interval in an effort to avoid collisions with transmissions from hidden wireless nodes. One example apparatus generally includes a receiver and a processing system. The receiver is typically configured to receive a multi-user (MU) transmission comprising at least one packet for the apparatus. The processing system is typically configured to determine a checksum of the at least one packet and to start an idle interval associated with the apparatus after receiving the MU transmission if the at least one packet comprises a frame check sequence (FCS) that corresponds to the checksum, wherein the idle interval includes at least enough time for transmission of an acknowledgment (ACK) frame. For certain aspects, the idle interval may comprise an extended interframe space (EIFS).