Am using a Mackie 1604 for live board and came across a noise problem last weekend. The monitor output is an unbalanced TR jack and was connected to a 100 snake via a 1/4 TRS jack. This fed a TRS input into my amp on stage for the monitors. Running the unbalanced TR output via a TRS feed 100' produced a noticable hum and white noise (this was not present on my main speakers fed via TRS balanced output from mackie 1604 main outputs). Unfortunately, there is no other TRS balanced output available on the Mackie with independent monitor volume control via a dedicated aux bus. Any ideas?