Didn't change much changing the bandwith.Are you able to change the channel bandwidth instead? That may help.
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Even though my connection was decent on the non DFS 5ghz channels, it seems even better on the DFS 5ghz channels as there is literally no one else in the neighborhood using these channels. Now i'm having second thoughts on using ethernet with decent performance on wifi.
Probably another thing others can look into if their router allows using DFS channels, and you don't live near an airport or somewhere with alot of stuff flying over you that could intefere.