Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

chenks

macrumors 65816
Original poster
Oct 23, 2007
1,187
489
UK
OK have a strange issue......

Hardware
- Livingroom AppleTV - 3rd Gen AppleTV (1080p) - v5.2.1 - Ethernet connected 100Mbit/s
- Bedroom AppleTV - 3rd Gen AppleTV (1080p) - v5.2.1 - Ethernet connected 100Mbit/s
- iTunes Library - Mac Mini (Mid 2001) ML 10.8.3 / iTunes 11.0.2 - Ethernet connected 100Mbit/s
- Router/switch - Sky Hub SR101 - Location Livingroom

Problem
I have 1080p locally stored content in iTunes that plays perfectly on the Livingroom ATV. I'll supply one example file for reference. 1920x800 @ 8754kbps, low complexity, file size around 9GB. This example starts playing after about 1 - 2 seconds, and plays perfectly on the Livingroom ATV. Flicking between chapters is almost instant.

If I attempt to play the same 1080p file (or any other 1080p files) on the Bedroom ATV then it sits with the spinning wheel and does nothing. I assume it would start playing eventually but i've never waited long enough to find out. SD and 720p content plays perfectly on this Bedroom ATV (see attached image).

Photo%2B14-04-2013%2B15%2B18%2B41.jpg


At first I though it might be a cable issue, so I tested the bandwidth across the ethernet link (using iperf) and the results are 95Mbps, so bandwidth across the ethernet link isn't a problem. I also tested the link using a different device and it was able to stream HD content no problems at all.

I also tested the bandwidth on the link the Livingroom ATV uses and that also gives 95Mbps (an expected result for a 100Mbps link).

Next test was to swap the ATV's location around to see if the fault followed the ATV or stayed at the location.
The fault stayed at the location, so the Livingroom ATV is now in the bedroom and that ATV now can't play 1080p content from iTunes.
Bedroom ATV now situated in the livingroom can play the 1080p content fine.

So that would suggest a problem with the ethernet link in the bedroom, but the bandwidth tests suggest otherwise. I also connecte my MBP to the bedroom ethernet link and the same 1080p file played fine on the MBP via Quicktime.

The cable run from the bedroom to the router (which is in the livingroom next to the Livingroom ATV) is around 20 meters (Cat5E cable terminated to wall sockets).

So...... any thoughts?
 

FreakinEurekan

macrumors 603
Sep 8, 2011
5,419
2,488
Next test was to swap the ATV's location around to see if the fault followed the ATV or stayed at the location.
The fault stayed at the location, so the Livingroom ATV is now in the bedroom and that ATV now can't play 1080p content from iTunes.
Bedroom ATV now situated in the livingroom can play the 1080p content fine.

So that would suggest a problem with the ethernet link in the bedroom, but the bandwidth tests suggest otherwise.

Nice to see some people still know how to do basic troubleshooting :)

Since you've eliminated the ATV device (it works on a different connection) and confirmed the problem on that connection with a second ATV device, it's almost certainly the connection. The only other thing could be something environmental to that location (e.g. RFI or power problem).

If feasible, string a long Ethernet through the house to that device, bypassing your installed cable run. If it works with that, you have absolutely isolated it to a cabling issue. If it fails with that, the cabling is fine & it's environmental.
 

roidy

macrumors 65816
Dec 30, 2008
1,027
22
Nottingham, UK
Does the Sky hub have wireless? If so try disconnecting the bedroom ATV from the ethernet and connect it to the network wirelessly and see what happens.
 

chenks

macrumors 65816
Original poster
Oct 23, 2007
1,187
489
UK
Nice to see some people still know how to do basic troubleshooting :)

Since you've eliminated the ATV device (it works on a different connection) and confirmed the problem on that connection with a second ATV device, it's almost certainly the connection. The only other thing could be something environmental to that location (e.g. RFI or power problem).

If feasible, string a long Ethernet through the house to that device, bypassing your installed cable run. If it works with that, you have absolutely isolated it to a cabling issue. If it fails with that, the cabling is fine & it's environmental.

that's the thing, i've tested the cabling with other devices it operates perfectly.
i even tested it with 2 gigabit devices at each end, ran iperf and the bandwidth test gave 980Mbps, so it appears the cabling is performing as expected.

i've connected other devices using the existing cabling and 1080p content streams normally. that's what makes this so confusing that the appletv cannot do it.

this was the last iperf test run on the cabling

------------------------------------------------------------
Client connecting to 10.0.1.3, TCP port 5001
TCP window size: 129 KByte (default)
------------------------------------------------------------
[ 4] local 10.0.1.99 port 60749 connected with 10.0.1.3 port 5001
[ ID] Interval Transfer Bandwidth
[ 4] 0.0- 1.0 sec 112 MBytes 935 Mbits/sec
[ 4] 1.0- 2.0 sec 111 MBytes 932 Mbits/sec
[ 4] 2.0- 3.0 sec 111 MBytes 933 Mbits/sec
[ 4] 3.0- 4.0 sec 111 MBytes 933 Mbits/sec
[ 4] 4.0- 5.0 sec 111 MBytes 932 Mbits/sec
[ 4] 5.0- 6.0 sec 111 MBytes 933 Mbits/sec
[ 4] 6.0- 7.0 sec 111 MBytes 933 Mbits/sec
[ 4] 7.0- 8.0 sec 111 MBytes 933 Mbits/sec
[ 4] 8.0- 9.0 sec 111 MBytes 933 Mbits/sec
[ 4] 0.0-10.0 sec 1.09 GBytes 933 Mbits/sec

Does the Sky hub have wireless? If so try disconnecting the bedroom ATV from the ethernet and connect it to the network wirelessly and see what happens.

wifi range in that room is poor so i wouldn't expect to be able to stream content with that high a bitrate.
 

Mrbobb

macrumors 603
Aug 27, 2012
5,009
209
U not doing silly static IP are u? No fine, I would reboot router + switch and let ALL devices re-learn their IPs.
 

chenks

macrumors 65816
Original poster
Oct 23, 2007
1,187
489
UK
U not doing silly static IP are u? No fine, I would reboot router + switch and let ALL devices re-learn their IPs.

all DHCP except the Mac Mini (iTunes Library) which has a router assigned static IP.
 

Mrbobb

macrumors 603
Aug 27, 2012
5,009
209
Change switch port if u haven't done so. Did u wire the CAT5 yourself, u followed EIA cable pairings correct? While spinning, look at the switch and make sure it's solidly on 100mbit and not 10.
 

chenks

macrumors 65816
Original poster
Oct 23, 2007
1,187
489
UK
Change switch port if u haven't done so. Did u wire the CAT5 yourself, u followed EIA cable pairings correct? While spinning, look at the switch and make sure it's solidly on 100mbit and not 10.

there is no switch, the router is the only network device.
yes wired myself and punched down as per cat5e spec.

iperf bandwidth tests show the cable is running correctly at 100Mbps and 1000Mbps (bandwidth report shown in previous post).

when testing the cable with other devices it streamed 1080p content fine, it just seems to be the appletv that can't for some reason.
 

chenks

macrumors 65816
Original poster
Oct 23, 2007
1,187
489
UK
I don't have a long enough cable at the moment to test alternate connection, but when I do I will to see what happens.

I'm still not convinced it's a cable problem though (even though everything points to it), as the iperf tests all give expected results.

Checked the router logs and it was rebooted 36 hours ago (due to firmware upgrade), so rebooting the router hasn't made any difference.
 

Mrbobb

macrumors 603
Aug 27, 2012
5,009
209
Assuming no layers 2-3 (MAC-IP) problem, then the remaing culprit is layer 1, the cable, which u can verify quickly if u can run a long extension as mentioned.

The ATV *may* (am reaching here) requires "tighter" layer-1 compliance.
 

FreeState

macrumors 68000
Jun 24, 2004
1,738
115
San Diego, CA
The other test your missing

Have you tried to move the actual TV set out to the other room to isolate it? Are the two sets the same model and brand? It is possible its a syncing issue of the TV set with 1080p material?
 

FreakinEurekan

macrumors 603
Sep 8, 2011
5,419
2,488
that's the thing, i've tested the cabling with other devices it operates perfectly.
i even tested it with 2 gigabit devices at each end, ran iperf and the bandwidth test gave 980Mbps, so it appears the cabling is performing as expected.

When you have eliminated the impossible, whatever remains, however improbable, must be the truth.
 

chenks

macrumors 65816
Original poster
Oct 23, 2007
1,187
489
UK
well i may have had a break-thru.
i decided to take a close look at the files, and noticed that they weren't optimised (for streaming).

i ran one of the files thru subler and optimised it, and it started to play normally on the problematic ATV.

what doesn't make sense though is why it was able to play fine on the other ATV even when it wasn't optimised.

i've only checked one file so far, so will go and check a few others and see what happens.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.