I have some users reporting slowness on a 9300 switch. The stats show large (several hundred thousand) transmit drops occurring in short bursts. The confusing thing is, there is often very little traffic going on when the transmit drops are happening. For example, one particular case happened this morning at 4:19am. Traffic through that port was under 100kbps the whole night. Not all users using this same switch are reporting issues. Could this be some sort of bug? We are running IOS-XE 16.6.5
Have a look at this link. This is a field notice with a bug ID on a memory leak that is affecting many versions. A bug usually affects the entire switch, and the strange part about yours is that you only have some users that are affected. If you move the affected users to different ports, does the problem persist?
Besides the possibility of a bug, your situation might also be representative of a very severe level of output dropping which can drive average transfer rate so low, it can seem that congestion cannot be an issue.