"Squelch" that background noise
Most handheld radios utilize the "squelch" control in order to filter out unwanted background noise. I am not familiar with your particular model, but this is how most of them generally operate. Turn your unit on, with the volume somewhere near the middle, and then turn the squelch control all the way up, until you are completely flooded with all that static and irritating, obnoxious background noise. Then slowly turn the squelch control down, until most of that noise is-"squelched," or suppressed. A good follow up action is to listen, and ensure that you can still hear all the other boats that are near you. If you can, then you have set it up properly. Best wishes, and smooth sailing from the SS Enterprise.