Hi Skymoose! I personally own a Droid RAZR M and I want you to enjoy yours as much as I enjoy mine.
Clearing the cache in the device memory should not affect the audio quality of your calls. It appears there may be another issue you're experiencing. Have you tried adjusting the audio volume while on a call? Is this happening with all calls or just intermittently? Do you have a device cover of case on your RAZR M? If so, please remove the cover/case and retest. Please let me know so that I can further assist. Thanks!
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