Run the check
Record a baseline with the device directly connected.
Repeat through the hub with the same app, tab, and device setting.
Add the usual hub load and check for disconnects or large pauses.
Read the result
Repeatable dropouts matter more than a tiny difference in browser timestamps.
Limits and next step
Scheduling noise prevents a reliable sub-millisecond hub latency verdict.
Repeat the check after changing one setting or connection. Keep a record of what changed before deciding whether the device needs service.