A user equipment, method and computer program for adjusting an effective centre frequency of channel filter in a user equipment to improve the adjacent selectivity when the network is transmitting on an irregular bandwidth channel and the user equipment is receiving the signal via a channel filter that has a wider pass band than the bandwidth of the channel. The method comprises filtering received wireless communication signals at a channel filter. Identifying a preferred centre frequency for the channel filter by: adjusting a centre frequency of the channel filter; determining a level of adjacent channel selectivity of signals filtered by the channel filter; comparing a level of adjacent channel selectivity at different centre frequencies of the channel filter; and identifying the preferred centre frequency as the centre frequency that provides a highest level of adjacent channel selectivity.