Question for all the experienced sdc users. I have hired one for a couple of days for the Missus to use but ended up using it more myself as I found a small patch with the 5000 and then used it to clean up bits I couldn't find, mainly because the ground was hot as hell. Got a few with 5000 and Sadie but ground noise drove me mad, could have dug the whole area. Main question is going to buy one and would like to know what most run on cause I started on 3 and got a few iffy signals then turned it to 5 and was a lot clearer but I don't think I could listen to the noise all day, I'd loose the plot. Also I only got about 5 hours on battery's, is this cause running hotter?