This Frequently Asked Questions (FAQ) document provides concise answers and guidance for using the Grandstream audio IP phones, the GRP261X Series. This FAQ is intended to assist administrators and users in resolving common issues and understanding key features.
Product Overview & Specifications
The GRP261X phone models come with different variants in each model. P indicates that it supports PoE, G indicates that the phone has a gigabit Ethernet port, and W indicates that the model supports Wi-Fi. All of the models that contain P, G, and W in their model names support PoE. If the GRP261X phone model does not have any letter and the end of the model name, it means that it does not support any of the aforementioned features.
Only the model variants that contain P, G, and W in their model name support PoE. E.g., GRP2612P, or GRP2612W.
Audio codecs supported: G7.29A/B, G.711µ/a-law, G.726, G.722 (wide-band), G. 723, iLBC, OPUS, in-band and out-of-band DTMF (in audio, RFC2833, SIP INFO), VAD, AEC, CNG, PLC, AJB, AGC.
Yes, GRP260X IP phones have a built-in HD speaker that can be used during calls.
Yes, you can host a 5-way audio conference for all the models, except GR2614 and GRP2615.
Yes, the user can connect a headset using an Electronic Hook Switch (EHS) using an RJ9 connector. E.g., Plantronics, Jabra, and Sennheiser headsets.
Setup & Registration
- GRP2610(P): 2 SIP Accounts, 2 Lines
- GRP2611G: 3 SIP Accounts, 3 Lines
- GRP2612(P/W/G): 4 SIP Accounts, 4 Lines
- GRP2613(W): 4 SIP Accounts, 6 Lines
- GRP2614: 12 SIP Accounts, 4 Lines
- GRP2615: 16 SIP Accounts, 10 Lines
- GRP2616: 16 SIP Accounts, 6 Lines
- GRP2624: 12 SIP Accounts, 8 Lines
- GRP2634: 12 SIP Accounts, 8 Lines
- GRP2636: 16 SIP Accounts, 12 Lines
- GRP2650: 16 SIP Accounts, 14 Lines
- GRP2670: 16 SIP Accounts, 12 Lines
Yes, if activated, the user can make a direct IP call to another IP phone.
Yes, if the registration of the extension fails on the primary server. The IP phone will attempt to register to a secondary server using the same SIP extension number and authentication password.
Yes, GRP261X IP phones can be connected and authenticated over PPPoE.
Provisioning can either be done through our cloud platform, GDMS Unified Communication via TR-069, or it can be provisioned using Grandstream IPPBXs using Zero Config.
Yes, the user can define the function of a soft key based on the context. For example, the user can set a soft key to perform a certain action depending on whether the phone is in the idle screen or in the call screen.
Yes, configuring the VLAN on the IP phone provides enhanced security by isolating the media traffic of the phone from the other traffic. This makes the management of the traffic, like quality of service, very easy.
GRP261X IP phones support QoS on both Layer 2 and Layer 3. On Layer 2, it supports 802.1p. On Layer 3, it supports ToS, DiffServ, and MPLS.
Calling Features & Line Management
Do Not Disturb can be enabled in multiple ways.
Using the LCD screen:
- Press the Menu button and navigate to “Settings > Call Settings > Do Not Disturb”.
- Use the RIGHT/LEFT keys to disable/enable DND.
- Press the “Save” softkey to save the change
Using the mute button:
Pressing the mute button while the phone is idle activates DND.
The GRP series phone supports the Alert-Info mapping to the 3 custom ringtone files. For example, if you configure the Matching Incoming Caller ID to “priority”, the ring tone will be used if we receive INVITE with Alert-Info header in the following format: Alert-Info:;info=priority
The GRP261X IP phone can store up to 2000 contacts on its local storage memory.
Yes, integration with LDAP allows the administrator to manage the contacts on the LDAP server, and the user can search the LDAP contact directory from the GRP261X IP phones.
Configuration, Provisioning, & Firmware
The device configuration interface can be accessed by following the steps below:
- Make sure that GRP261X boots up and is connected to the network.
- To display the IP address, press and hold the UP button on the keypad.
- Enter the IP address of the device in the browser.
- The default administrator username is “admin”, and the password can be found on the label at the bottom of the device.
The current firmware version of the device can be found on the web UI and LCD menu:
– Web UI: Status > System Info > System Version
– LCD: Settings > Status > System > System Version.
GRP261X supports firmware upgrade via the following methods:
- Method 1: Upload the firmware file
Manually upload the firmware file through the device Web UI to perform the upgrade (supported for applicable firmware versions only).
- Method 2: Using a firmware server (HTTP/HTTPS/TFTP/FTP/FTPS)
Configure the device to retrieve and install firmware from a remote server using supported protocols: HTTP, HTTPS, TFTP, FTP or FTPS.
The firmware server address can be provisioned manually in the Web UI or automatically via DHCP options (for example, Option 66 or Option 160, depending on deployment).
- Method 3: Using GDMS
Upgrade firmware centrally via GDMS (Grandstream Device Management System), enabling remote, batch, and scheduled firmware management.
To save a backup file of the configuration of the GRP261X IP phone, please follow the steps mentioned below.
- Access the webUI and use the administrator’s credentials to log in.
- Navigate to Maintenance > Upgrade and Provisioning
- Click on “Download Device Configuration” to download the configuration file in .txt format. The user also downloads the config file in xml format.
Password can be configured from the LCD menu and the web UI:
– LCD: Preferences > Keypad Lock.
– Web UI: System Settings > Security Settings > Keypad Lock.
Troubleshooting & Maintenance
A factory reset could be executed from the web UI or LCD menu.
– Web UI: Maintenance ->Upgrade->Advanced settings->Factory Reset.
– LCD: Settings->Advanced->Factory Reset.
You should make sure that the phone is connected to the network and that it is able to obtain an IP address. Secondly, check if the account is set to active by setting the “Account Active” configuration in the Account page of the web interface to “Yes”. Additionally, check if the login information and the SIP server are correct. If the SIP server is wrong, the phone cannot contact the SIP server for registration. If the login information is wrong, the SIP server will reject the registration request of the phone.
If all of the above are correct, there may be a problem with NAT traversal. If the GXP21xx is on a LAN and needs to register to a SIP server on a public IP, please enable NAT traversal by selecting the NAT traversal method according to your network environment. If you are unsure, it is recommended to select “Auto” to enable the automatic NAT traversal configuration feature.
When this situation occurs, please check if the handset is securely connected. If it is not, please reconnect it. It could also be caused by the following:
- The other party may have pressed the “Mute” key, which will place the call on mute. Please tell the other party to check if Mute is on and unmute the call.
- If your phone is connected to the Internet through a router, this can be caused by the NAT traversal issue. If the GRP261X is on a LAN and needs to register with a SIP server on a public IP, please enable NAT traversal by selecting the NAT traversal method according to your network environment. If you are unsure, it is recommended to select “Auto” to enable the automatic NAT traversal configuration feature.