[DG] DF4 pro weird readings and depth scale issue

hello,

i have some issues on my df4pro since i purchased it.
First the "depth scale" on both down and sonar vision always differs from the depth shown on the top left and is shown correct in the wifish app.

The second issue isthat i sometimes get readings with double numbers on this scale like 0 meters 0 meters and so on.
anyone has had this issues and can help me solve it? The transducer always mounted with a portable holder about 0,5 meters below surface. i added 4 attachments showing the same screen on the df4 and wifish, and 2 of these weird reading stuff.

excuse my bad english and thanks in advance

http://forum.raymarine.com/attachment.php?aid=1757
http://forum.raymarine.com/attachment.php?aid=1758
http://forum.raymarine.com/attachment.php?aid=1759
http://forum.raymarine.com/attachment.php?aid=1760
http://forum.raymarine.com/attachment.php?aid=1761

  weird_readings2.JPG (Size: 362.39 KB / Downloads: 0)

  weird_readings1.JPG (Size: 423.28 KB / Downloads: 2)

  wifish_scale2.png (Size: 274.65 KB / Downloads: 2)

  dragonfly_scale2.JPG (Size: 435.45 KB / Downloads: 2)

  dragonfly_scale1.JPG (Size: 474.06 KB / Downloads: 2)

  wifish_scale1.jpg (Size: 89 KB / Downloads: 2)