Nighthawk Router R7000 and Cisco SPA504g

[SarcasticWit]

I am trying to use a Cisco SPA504G phone with my Nighthawk Router for remote work, but have been unsuccessfull in getting them to work together.

My router firmware is current with version V1.0.9.88_10.2.88

I have also disabled/turned off the SIP LG as noted in the article at:

https://kb.netgear.com/30796/How-do-I-disable-SIP-ALG-on-my-NETGEAR-device-using-the-router-web-inte...

but this made no difference...

I can see the SPA connected, and allowed, however I cannot make or receive calls...

I work for an internet company and my techs are telling me that I the device is registering in our switch...

I can get the phone to work if it has a direct connection to my internet connection, or even going through a basic 4 port Cisco switch, so I am at a loss why I cannot get my router and my phone to play nice together...

Any thoughts, tip or tricks anyone can suggest?

Many thanks in advance...

[antinode]

> Model: R7000|AC1900 Smart WIFI Router

   Connected to what?

> [...] have been unsuccessfull in getting them to work together. [...]

   None of that is a useful problem description.  It does not say what
you did.  It does not say what happened when you did it.  As usual,
showing actual actions (commands) with their actual results (error
messages, LED indicators, ...) can be more helpful than vague
descriptions or interpretations.

> My router firmware is current with version V1.0.9.88_10.2.88

   Says who?  You might try one or more of the newer versions.  Among
older versions, V1.0.9.42_10.2.44 was found to be pretty satisfactory by
many.

   Visit http://netgear.com/support , put in your model number, and look
for Downloads.  (For older versions, under Firmware and Software
Downloads, look for "View Previous Versions".)  Find the kit(s).
Download the kit(s) you want.  Read the "Release Notes" file for
instructions.  (In the User Manual, look for "firmware", and,
especially, for a topic like "Manually Upload Firmware to the Router".)
When that fails because of a deficient User Manual, try:

      https://kb.netgear.com/23960

> I work for an internet company and my techs are telling me that I the
> device is registering in our switch...

   I know not what that means.

> [...] going through a basic 4 port Cisco switch, [...]

   If I were to do a Web search for "a basic 4 port Cisco switch", would
I be likely to learn the model number of that device, or how you're
connecting it to what?

> Any thoughts, tip or tricks anyone can suggest?

   Try different/newer/older firmware?  Identify your equipment and
describe how it's all connected?  (Hint: If a device has different types
of Ethernet ports, then "connected to device" is not enough detail.)
Describe the actual symptoms (beyond "not working")?