We experimentally demonstrate the influence of a high power continuous wave (CW), as a holding beam (HB), injection into an SOA at the gain transparency wavelength on the device static and dynamic performances over a wide range of signal wavelength. Besides, the obtained results are exploited in an SOA based multi-channel transmission system to reduce the cross-gain modulation (XGM) induced inter-channel crosstalk pattern penalty between signals. Experiment shows that this crosstalk penalty can be considerably reduced by the HB injection at the gain transparency wavelength.