There is a setting in the App that should let you fix this. Assuming you are using the NEST app go into it and look at the video from the doorbell. Then hit setting (Gear) icon in the upper right corner. Scroll all the way down until you see your doorbell icon and touch it. Next scroll all the way down and you should see "CHIME DURATION". There is a setting that says "Do you have an electronic Chime". If it is off then turn it ON and then you can set the Chime Duration. You should be able to set it to about 1 second and this should fix the problem.
Hope this helps
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