I've never had your model, but you should be able to try a few things.
Just an FYI.....the "fish symbol" setting usually automatically sets alot of your other settings.....think it as a setting for newbs perhaps.
1. Try adjusting your sensitivity setting. Tune it to where you just make the majority of the noise disappear.
2. Make sure your are set for the salt of freshwater setting.
3. Make sure you didnt get any bubbles in your "glue" used on the transducer.
4. If it is dual beam transducer and you stay in shallower water, think about using only the most sensitive for your depth. One beam will also be much wider and may not be the most sensitive....so its a bit of a balance.
If you get your settings right, you may even be able to see thermoclines (temp changes) in the water column.
Keep in mind though that these settings wont be the same all year or even day to day sometimes.
Things change and the sensitivity will need to be constantly adjusted. Most of the other settings will be a standard though.
Basically, grab the manual, go through each page and set the defaults to your needs....in the process, you will see which settings will need to be toyed with more than others.
Good luck, and good fishing.
Don't lead me to temptation, I already know the way.