Macbook Air Experiences Slow Wi-Fi (and only on my home network)

My Macbook Air (Mid 2012) is running OSX 10.10.3 (1.8 GHz i5 and 8 GB ram). I work from home and have been having terrible audio streaming issues (cutting out, fading, etc). This is voip only so I did some initial troubleshooting. I found fairly quickly, though, that I don't think it's any peripheral (same issues between browsers, headsets, etc). I started thinking it was the wifi and did some tests:

• On the home network my phone runs ~25 mbps, a windows laptop ~28 mbps, and a desktop mac ~ 30 mbps. My Air at the same time will bounce from 3 to about 13 (max)
• I have tried connecting my computer to my phone's hotspot and it pulls ~20 consistently and allows me to have meetings and no audio issues. Because of this I think my issue is wifi based (causing audio issues)
• I have read through a lot of forums/discussions and have tried changing my wireless channel (Comcast says it's technically not possible), a complete OSX reinstall (not time machine, I wiped it), and have removed my wireless network and re added it (along with restarting the router approximately 9 million times)

At this point I'm a little stuck. I feel like I've read through a ton of comments and posts and am not sure what else it could be or how to fix it. I'm happy to run through more diagnostic tests or trials if anyone has any suggestions!