Peepers have an extremely loud call, often distorting my ears. My frog call recorders get overdriven as well. I am glad that you posted, I thought I was the only that gets fooled by their call. When I first got into herps I spent 30 min looking for a gray tf in emergent vegetation but I was totally looking in the wrong place! My advice for finding them is going out when it is totally dark because they tend to call even when disturbed. Don't use a bright flashlight to minimize disturbance, and look in tussocks or grass clumps. I use a snake hook to pull them apart and they don't usually jump away.