The best contact for the log often depends on getting that callsign. You get mad too when you nearly have it but QRN, QSB and other HF diseases cheat you of claiming the contact? I tried a variety of analog filters, notches, pulse clippers, and the rig's noise reducer, RF gain, PBT..., but wondered if a user controlled computer digital processor running on the audio out from the rig might run circles round the old methods. It does! I'm sure there are many such apps but I had initial success with "PulseEffects" for Linux. It picks up the USB audio out from the rig (IC-7610) and outputs to an outboard speaker by the rig. There are so many adjustable possibilities available I'll not list them all, but if you start with the input and output filters in their default order and settings, enabling from the top of the list all that look useful, the effect is a spectacular clean-up and improved intelligibility. You can then tweak to even better. There's a catch -easily solved: PulseEffects expects to work on the output of a computer app, but the rig USB audio is not an app. If the Test Signals button is selected, the rig output can be selected in sound preferences as Analog Input PCM2901 Audio Codec or similar. It now plays through PulseEffects with any or all processing wanted. PulseEffects was originally intended to improve notebook crappy speakers and audio, but it does so much more on HF audio. -And it's free. There must be similar apps for Win and Mac?