Passenger window problem

#1
I've noticed since I bought my car that when I drive the passenger side window tends to creep down and I have to hit the switch to bring it back up. It doesn't come down a lot but enough to hear the wind whistle through it. I'm not sure if this is motor or regulator issue or what. Has anyone else encountered this problem?? What did you do to fix it??
Thanks in advance for any and all help!!
 
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