Here is my 880L WAN port speedtest.net results: v1.05WW
After factory reset using default settings, no QoS changes:
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Setting QoS to 100/3 and no PC placed in QoS priority section:
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Setting QoS to 100/3 and wired Mac Book Pro OSX 10.10.5 placed in Highest section:
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Setting QoS to 120/3 and wired Mac Book Pro OSX 10.10.5 placed in Highest section:
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My 880L is connected to my DIR-890L using it's DMZ so theres nothing on the 890L interfering with the 880L connected on it's WAN port.