Apple tv duplicates name on network

I have a recurrent issue I can't get hold of.

On my home LAN I connect with my MacBook Pro, my iOS devices and an Apple TV (2nd series).

All this via a TimeCapsule and relevant modem.

I can often see the name of the Apple TV automatically adding a incremental suffix starting with Apple TV (1), Apple TV (2) ... Apple TV (10) and so on.

I have noticed this also a few times with my MacBook where the network name was being changed by adding a progressive number.

Sometimes stopping all devices and starting the network again fixes the issue, sometimes the Apple TV (XX) network name seems to be memorized into all devices and I have to manually rename the unit.

Everithing else appears to be working normally.

I guess some settings are wrong and the Apple TV name is being echoed on the network repetedly. Once it went up to Apple TV (99)!!

Any idea what's going on here?

Thanks and regards

Pieter