Using Cisco CP-8800 VoIP phones connected to EX7000/AC1900 WiFi Range Extender

[camp1023]

I recently upgraded my home office and purchased a EX7000 WiFi Extender.  Initially I was having issues with connectivity and had to downgrade my firmware version to V1.0.1.84_1.0.148.  All seems to working well now except my office phones working via MRA (Mobile and Remote Access).  

My two Cisco CP-8800 series phones are directly connected to the extender and are successfully connecting to their source networks. The intermittent issue I have is during conversations the audio traffic will drop for a about 10 seconds and then return.   I believe the root cause may be QoS but have no way of prioritizing the voice traffic through the extender.  

Has anyone run into this issue and know of a way to resolve it? 

[DexterJB]

Does the issue persist if you bypass the EX700 and connect the phones straight to your router?

[camp1023]

I have not connected the Cisco CP-8800 series IP phones directly to my AT&T DSL Fiber router. 
Previously, the Cisco endpoints were directly connected to a NetGear WN2000RPTv3 Extender and never had any audio (traffic) issues. 

[DexterJB]

That's something that you can try to help us isolate the issue. Let us know how it goes.

[camp1023]

The issue does not replicate when directly connected to my DSL/Fiber router.   It is persistent when connected to the Netgear EX700/AC1900 Extender on both Cisco (CP-8811 & CP-8841) IP phones. 

Thank you