The box under the TV is on the LAN via an access point running in WiFi client mode. I chose this route after unsuccessfully trying to find out which USB WiFi adapters are supported by Linux drivers AND locally available (I still haven’t got a clue about the right answer to that question).

The connection has been very bad. No proper data rates, lots of lost packets. I just relocated the AP from under the TV (on top of the DVD player and next to the computer) to the upper back of the TV. It’s like Christmas now. No more problems, the torrents immediately started running faster AND I’m copying a gallery from the laptop (literally) to the machine at near-maximum rate. I’m in heaven. Again. Even the headache is gone.