There were input errors. But why didn’t it show on the wired side?

Feeling a bit dumb and a little confused. I had users in a certain area of one of my sites that were complaining of slow WiFi. It’s a corner of a building where 3 Aruba APs reside and an IDF feeding this area and those APs.

I gathered intel, which of course just 3-4 people mention “super slow WiFi.” No one mentions slow desktop (wired) connections and a technician had moved two of the users from wireless to wired connections to get them going until I got on site. I plugged in and ran some speed tests on wired and wireless and they would range but nothing unacceptable. It definitely had slow speeds on WiFi but always over 30mbps. I can typically get 130mpbs in the test laptop.

The culprit: embarrassingly, it took me an hour to track down the issue as one ports on the switch had a lot of input errors. It was one of the port channel uplinks. I temporarily disabled the link and monitored and things improved. Later I tracked down a bad fiber patch and swapped it out and they were good to go. I honestly forget to check interface issues because we have rock-solid connections and this is only the 2nd time in about a decade that the issue was a cable (and presented with interface counters). I know that’s super basic troubleshooting and I should always lead with that but being that it’s so rare for me to see a problem, I kinda forgot

My question: I focused a lot of my troubleshooting on wireless and those 3 APs because wiring the connections “fixed” their issue and all of the complaints were about WiFi. When my wired speed tests were passable, I began concentrating on WiFi. Can someone theorize why the wired connections would have hid this issue while the WiFi connections struggled so much with the input errors? I’m just curious for my notes, future issues, and just learning why the problem didn’t show equally on wired connections. I know online speed tests aren’t the best troubleshooting strategy but I was beginning iperf tests when I decided to check interface stats. Next would have been packet captures along the route.

Feel free to jump on me about my terrible troubleshooting skills but also helping me figure out why it presented this way is much appreciated.

Thanks in advance!