NAIM UnitiLite - Page 9

Page 9 of 15 26/03/2010
NaimUniti Troubleshooting Guide.doc
4.8
4.84.8
4.8 Cannot j
Cannot jCannot j
Cannot jump lists when using UPnP server
ump lists when using UPnP serverump lists when using UPnP server
ump lists when using UPnP server
• Some UPnP servers do not return the browse data in alphabetically sorted lists. If this
is the case then the Uniti cannot perform an alphabetical jump to a position in the
list.
4.9
4.94.9
4.9 Wired UPnP
Wired UPnP Wired UPnP
Wired UPnP –
––
– troubleshooting
troubleshooting troubleshooting
troubleshooting
From Naim experience so far UPnP streaming problems on a wired connection fall into
3 different camps:
1. Firewall and devices filtering traffic - either in the ADSL modem or the PC has its
software firewall setup aggressively.
2. NAS's that when doing other tasks cannot achieve the necessary throughout rates
of streaming.
3. Power management
1. Can be proved by using a hub and as a test, disable any software firewalls running
(eg. Windows Firewall).
2. On some NAS devices when they rescan their music library to populate the built-in
UPnP servers database, they use up so much CPU time they cannot actually stream
music. To stream reliably a 44.1/16 WAV the NAS must be able to supply on average
176.4KBytes/Sec. That doesn't sound much, but often throughput on cheap NASs can
go down to a trickle when doing background tasks. On Uniti we pre-buffer 4 seconds
of data before playing audio and aim to try and keep that buffer full with 8 seconds
worth of audio at 44.1/16 WAV. As audio playback is a realtime task, it will show up a
weaknesses in a NAS, that otherwise would be ok just for storing files for casual
browsing.
Naim have written a PC application that simulates the read requirements of HDX (and
also can work for Uniti). It then measures all the throughputs over a configurable
period of time and will tell you if the system will stream reliably. Naturally the app can't
tell you exactly where the bottleneck is, but it does give a wealth of measured metrics
and also gives users confidence that their systems will stream reliably every time.
3. If a device goes to sleep (spins down hard drives, reduce CPU clock speeds etc),
then the wake up time on some budget NASs can be a long time (often more than
15secs). This in turn can make the Uniti think the device is faulty. For a consistent
streaming experience turn off any power management features on the NAS.
4.10
4.104.10
4.10 Hi
HiHi
Hi-
--
-Res music files drop out
Res music files drop out Res music files drop out
Res music files drop out
• Music files with a bit rate higher than 24/48 are not supported if using a
wireless connection. With a good signal in a non-densely wireless
populated area they should play with little problem but wireless conflicts,