Calibrating IR obstacle sensor

I have the GalaxyRVR kit I put together yesterday and having trouble with one of the two IR obstacle sensors. The first I was able to calibrate with 3 or 4 adjustments so it detected an obstacle, the original box, at about 20 cm and did not detect it at 30 cm. I’ve spent probably 30-40 minutes adjusting the second and can’t get it to reliably detect something that is there or not detect when nothing is there. Following the same procedure I can tune to sensitivity so it is just on at 20 cm but then as I move the box further away, or even take it fully away so nothing is within 1 meter, the sensor continues to detect (the led on-board flickers and it often returns TRUE to the arduino). If I adjust either of the potentiometers so it doesn’t detect at long distance, then it won’t detect an obstacle until only <10 cm away.
I’ve temporarily worked around this be rewriting the code so that it has to have 3 consecutive responses of an obstacle before responding and this has largely solved the problem.
Any thoughts on a better way to do the adjustment or is this a sign the sensor is bad? I did notice that on the one having trouble, the receiver was soldered on with about 1 cm of leads showing while the one that works has almost no leads showing.
Thanks for any ideas.

Please provide a screenshot of the error so that we can analyze and help resolve the problem

I made a short video showing the flickering even when the obstacle is out of the line of sight. This shows the left sensor working correctly and the right sensor having the flickering problem.

Please follow the steps in the tutorial link to adjust the detection distance and see if you can adjust it properly.
If the problem sensor still cannot be adjusted, it’s possible the sensor is faulty.
We will arrange to have a replacement sensor sent to you.
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