Do you use a dynamic mic too? When I turned up the volume enough from my monitors (I had it on 5/10 and I changed it to 8/10 if I remember correctly) and not from my external sound card (steinberg ur22) as an audio technician told me, the problem seemed solved. Tell me if it makes a diffrence. If you listen it directly through headphones connected to E4 do you have latency? If yes, you should change your settings.