I have found that after using the echo effect I am getting clicks and pops on that track. Is this common?
Yes, and there can be several causes. The top one is DC or battery voltage mixed into the show. You can remove DC from all your clips before editing in 1.2 with Effect > Normalize > Remove DC (deselect everything else). 1.3 users it’s either under Effect > Utilities or just Effect. The tool wanders between versions.
You can’t do this after editing. If you have a finished timeline, it’s too late. I have one capture device that adds DC to all its clips and it’s impossible to edit without taking it out.
The other possibility is a bad mismatch between audio clips. If you’re using a number of different standard clips in your piece, there can be a bad interaction between them. You could also have a broken clip. One bad clip in the system will cause ripple effects all over.
If the track level is being pushed too high (right up to the top and bottom of the track) that will cause bad sound problems as well.