Smart grid applications are going to reach the low voltage grid assets and households in order to efficiently use the resources in electrical distribution grids. A cost effective way to connect these devices is to utilize the existing network infrastructure or Power-Line Communication (PLC). In this work, we illustrate the impact of changing communication properties on a power balancing controller used to support frequency control in the setting of a microgrid. More specifically, we focus on PLC communication and show how time-varying delays can affect the control algorithm performance. Further, we propose and compare two different delay estimation techniques and demonstrate how the control algorithm can use this information to adapt its gains - yielding significantly better control performance, compared to the controller using static gains.