Since this is a decade old laptop I do think it would need a more thorough fan clean. This requires flipping the motherboard around to unscrew the fan as seen here [URL] A surprising amount of dust can clump up there which might be a problem. If there's a way to open up the metal case protecting the fins, I'd recommend it. What you're describing with zoom sounds like the built-in audio processing trying to counteract room noise. This is controlled by the 5537's MaxxAudio program (or "Dell Audio by Realtek"). Open that, go to Microphone and turn off all the options there, so no microphone processing is going on. Can't help you with the keyboard issue, but if you diassemble to clean the fan, make sure the keyboard ribbon connector is clean and slotted in tightly when you reassemble it. And then make sure all your drivers are up to date: [URL]
My Inspiron 15R 5537 is several years old.  It's got an i7, 16GB RAM, SSD, and I recently did a fresh install of Windows 10 Home.  All Windows updates are applied and Dell SupportAssist updates are current. I have ongoing issues and have tried everything I can find to fix them: 1) Several times a day, the fan will start racing loudly and the computer freezes for the short time the fan is going.  The racing fan only lasts a few seconds, but the fan sound and the freezing interrupts everything.  This Inspiron is used for web browsing (Chrome), Office 365 and Zoom.  The bottom of the laptop does not seem excessively hot.  If the racing fan happens when on a Zoom call or watching a video in the browser, there is a loud, buzzing noise in the speakers in addition to the fan noise and freezing.  I have used an air blower to clean out the vents, but that has done nothing. 2) The keyboard randomly freezes for no apparent reason.  Rebooting restores it.  This is highly inconvenient and frustrating. 3) A couple of months ago, I purchased a new Inspiron 16 with Windows 11.  I ran into a serious problem--the sound on Zoom calls cut in and out when there was music and singing or talking happening at the same time.  This does not happen on the Inspiron 15R with Windows 10.  I spent literally hours on the phone with Dell tech support, but they could not fix it.  I had to return the laptop.  Everything was the same except Win10 vs. Win11.  The old 15R problems are getting bad enough now that I am looking to buy an XPS and cross my fingers that Zoom will work properly on that with Win11.  (I should note that I posted about this on the Zoom support site and others have had this issue with Dell laptops.  After returning the Win11 Inspiron 16, I saw on the Zoom forum that the issue was a bad RealTek sound driver.  I wish I'd seen that before returning the PC.) Maybe someone here can help with my two issues--fan and keyboard--and save me from having to purchase a new laptop.  Other than those two issues the 15R works fine. Also, maybe someone here has experience with Zoom and Win11 on either XPS or Inspiron in an environment where there is music playing along with singing or talking, and whether the sound cuts in and out.  If you did have that problem, how did you fix it?  Sound driver? Thanks for any help. John
Inspiron 15R 5537 on its last dying breath & I've tried everything