Here's an update. I'm lucky. My ATV has been working perfectly well plugged into the modem/router with an ethernet cable to which my computer and iPhone are connected wirelessly.
I use it mostly to stream music and radio from mycomputer to the stereo system that plays around the house. Occasionally, I stream a movie from the Internet or from my computer. It has all been working just fine.
Yesterday, like so many hapless users around the world, I was pathetically excited by the announcement of an updated operating system for the ATV. I installed it and pulled the ethernet cable out. Immediately I had a connection.
All went well for a while: I streamed the radio and music. I was actually using two sets of speakers—the stereo connected to the ATV via AirPlay and another set plugged directly into the computer. After awhile, I realised the stereo was not working. Sure enough, the connection between computer and ATV was lost. I tried reconnecting but with no result until I reset the ATV. The connection was re-established and it ran happily for the rest of the day.
In the evening I turned off the music, put the ATV to sleep and eventually the computer hibernated. As did I.
This morning when I restarted the computer, I could not establish a connection—neither from the computer nor my iPhone. I should say that I usually just start the radio or music in iTunes and the ATV wakes up and goes about its business; I don't have to turn it on.
Trying not to reset it, I turned on the ATV with the remote. Nothing happened. I tried restarting iTunes. Still nothing. I then plugged in the ethernet cable and, bingo, it reconnected immediately with AirPlay icons showing on both the computer and the iPhone. A wee while later, just for the **** of it, I pulled out the cable and, after a brief, pause, a wireless connection established itself. The system has been running happily on the wireless since then. Trying to emulate the fault, I tried disconnecting, putting the ATV to sleep, hibernating the computer and then restarting, but the connection re-established itself immediately.
I don't know whether the ATV goes into some deeper sleep cycle after a time, or whether iTunes or some driver on the computer is affected by the computer going to sleep then hibernating, but it would be less than satisfactory if one had to reconnect to the ethernet or reset the ATV in order to make the thing work properly on the wireless network. If the problem recurs, I won't bother; I'll just reconnect the ethernet and await the next OS update.
I suppose, though, there's some very faint hope that this tale will provide a clue to someone better versed in the detailed workings of the technology than me. I hope so.
I'll also say—as one who has had an ATV2 that functions well, albeit only via ethernet—that it's a great thing. The ability to stream music, radio and video from the computer and the internet, all controlled from anywhere in the house by an app on the iPhone should I want to, is just fantastic. The ability to hire movies quickly and easily over the internet and watch them on demand is also great. I don't pretend to understand the problem with the wireless connection, but I'd be pretty sure Apple will figureit out and we'll all have an inexpensive and thoroughly useful gadget.
My thanks for the advice from others on this forum that has helped me get mine working. My commiserations to all those of you deeply frustrated by being unable to get yours' to work.
Cheers
PS This is completely unrelated to the problem of the ATV2's connection, but I wrote this post in a word processor and then copied it into this site. Random spaces between words simply disappeared.
Go figure.
