Power Line Communications (PLC) device for enhanced carrier sense multiple access (CSMA) protocols are described. The PLC device includes a modem, an AC interface and a PLC engine. The engine is configured for transmitting PLC packets over a plurality of electrical wires using a particular channel. Transmitting a normal priority packet may include attempting to access a communications channel to transmit a frame after a backoff time proportional to a randomly generated number within a contention window (CW), the CW having an initial value carried over from a previous transmission of a different frame. Additionally or alternatively, some of techniques described herein may facilitate the spreading of the time over which devices attempt to transmit packets, thereby reducing the probability of collisions using, for example, Additive Decrease Multiplicative Increase (ADMI) mechanisms.