Hi all, just having a bit of trouble with my furumo fcv582l. When in deep water,110m+, it wont read anything. Just a blue screen. As if you have the depth on 10m and are fish in 20m.I fish with it on manual, have adjusted my gain-when i turn it right up i just get clutter,tried each frequency,zoom,bottom lock,scroll speed,tx power,when i come back to 80m she comes back on and reads as normal.I used to have a fcv 620l and it worked fine up to 200m although wouldnt pich up fish at that depth but would read bottom and pick up mid water fish.I am using the same transducer for this new sounder (600w)Any help would be really appreciated.Cheers guys!!!!!!!!!!!!!!!!!!!!