Cisco 8832 User Manual page 59

We recommend that you use good-quality external devices that are shielded against unwanted radio frequency
(RF) and audio frequency (AF) signals. External devices include headsets, cables, and connectors.
Depending on the quality of these devices and their proximity to other devices, such as mobile phones or two-
way radios, some audio noise may still occur. In these cases, we recommend that you take one or more of these
actions:
Move the external device away from the source of the RF or AF signals.
Route the external device cables away from the source of the RF or AF signals.
Use shielded cables for the external device, or use cables with a better shield and connector.
Shorten the length of the external device cable.
Apply ferrites or other such devices on the cables for the external device.
Cisco cannot guarantee the performance of external devices, cables, and connectors.
In European Union countries, use only external speakers, microphones, and headsets that are fully compliant with
the EMC Directive [89/336/EC].
You can provide power to your phone in one of two ways:
Use the power adapter that comes with your phone.
If your network supports Power over Ethernet (PoE), you can plug your phone into the network. Plug an
Ethernet cable into the Ethernet phone port
If you are not sure whether your network supports PoE, check with your administrator.
Anything that degrades network performance can affect phone voice and video quality, and in some cases, can
cause a call to drop. Sources of network degradation can include, but are not limited to, the following
activities:
Administrative tasks, such as an internal port scan or security scan
Attacks that occur on your network, such as a Denial of Service attack
and into the network.