Hello TP link official support and community,

I have been using Deco XE75 V1 since 2 years now and have been very satisfied. Bufferbloat performance has been good with low latencies under load. I always got an "A" on the waveform bufferbloat test with the V1 hardware even when hopping over 2 nodes.

I recently bought three additional XE75 units and added to my mesh Wifi network; the new ones I received were the V3 Hardware. The main Deco unit was still always the V1 connected to my modem. Everything was fine until I decided to switch the main Deco unit from V1 to V3: I noticed that the latency performance went down to "C" on the test. The loaded latency test results with V3 hardware during upload were adding more than +100ms compared to V1 hardware. I tried all options like turning off QoS etc but nothing changed. I then reverted back to V1 as my main Deco and everything is back to normal.

I understand that the V3 firmware is less mature than V1; and it seems on V3 QoS is currently not implemented as toggling the QoS settings in the app has no effect. Actually I noticed that V1 performance (QoS off) is similar to V3 (QoS on or off, no change). But when V1 has QoS turned on, it reduces the loaded latency during upload by at least 100ms.

I hope this issue will be resolved in a future FW update on the V3 XE75 Deco units.