You will get better and more "in-depth" answers in the Electronics Forum, but you have to remember that the SI and DI are just very thin slices of sonar, so it will be very hard to "see" a bait. The 2d (traditional) sonar is a cone shape and if you drop bait next to transducer, you should be able to spot it. You may be seeing fish on your DI/SI and not realize it. There are lots of screenshots on the electronics forum and you will see exactly how fish look