A method of improvement for gain control for a Quadrature Amplitude Modulation (QAM) signal within a communication system with at least one digital modem. The communication system utilizes a non-decision aided AGC at the intermediate frequency level and a modified Adaptive Time Domain Equalizer (ADTE) to fine tune the level of baseband signals, perform phase and amplitude correction, and channel equalization. The center tap coefficients of or dynamically modified by the ADTE. The resynchronization time and phase and amplitude imbalance correction will be reduced as a consequence of the controlling of the signal gain by a non-decision aided automatic gain controller.