Wireless access speed is very slow(Wireless connection is poor)

This is anarticle based on a customer case. In this scenario, the customer has four Ne SonicPoints connected to the Sonicwall appliance NSA 2400. The SonicPoints works in 2.4GHz on channel 1, 6, 11, 13 respectively and the configuration looks good. However, the wireless client connectivity is really poor. There is a 2 to 3 seconds delay while ping from the wireless client to the gateway(NSA 2400 Lan interface).

Troubleshooting:

To troubleshoot this problem, following the steps below:

1, Check the status of all the SonicPoints. Navigate to SonicPonit > SonicPoints, scroll down to the bottom of the page. The status should be Operational.

The screenshot below shows the results of a recent scan. In this case there are more than 160 access points around the SonicPoints.

Navigate to SonicPoint > RF Analysis, it indicates that the RF Score is 1 which is the lowest, and the channels are overwhelmed. All that means the RF environment is really complex and highly interfered.

Resolution or Workaround:

To resolve this issue, trying to choose difference channels would be useless since there are too many third-party access points with strong signals in the building.
Nevertheless there are Wnk/Vap branches release to enhance the signal strength of the SonicPoint which can improve the connectivity and resolve the problem.
For Gen5, Wnk release is based on 5.9.0.4 and with many wireless issues fixed. Vap release is based on 5.9.0.6 with as same wireless fixes as wnk release and with vap enhancement in addition. So far it is combined to 5.9.0.7_17o as well.
For Gen6, the corresponding release is related to HF140677. And so far it is combined to 6.2.2.0-12n? as well.
So to overcome such issue, please upgrade to the latest version, or contact customer support to get the appropriate release.