Ping to router intermittent request timed out

Hi.

I have just upgraded to Comcast Gig service and purchased a XR500 router and Netgear CM1000-1AZNAS modem.

I first noticed a few issues with wifi dropping out. I came and checked my router and all lights were normal. I tried on my PC which is wired and that did not work either (I believe it was showing connected no faults but may be wrong, I think I could ping router from pc). I plugged my pc straight into the back of the modem and it worked fine, plugged back into router and nothing. A few minutes later it started working again. Lights never changed state always white. This made me run a ping test from my pc to router over the space of 12 hours and I lost 7 packets. I believe they were singular and spread out but I couldn't trace the history through the whole test but I did see 1 or 2 spread out. This prompted me to get my router replaced from amazon.

I've had the new router connected for a day now and have not witnessed any service drop outs thus far. But if I run a ping test to my router from my wired pc or wifi laptop I still drop  packets singulary every now and then. Here's the weird part though, I also set up a ping to www.google.com to run simultaneously with ping to router and I lost 0 packets on my pc.

Here are the results from PC

Router :

Ping statistics for 192.168.1.1:
Packets: Sent = 30388, Received = 30384, Lost = 4 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 263ms, Average = 0ms

Google:

Ping statistics for 216.239.38.117:
Packets: Sent = 30397, Received = 30397, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 16ms, Maximum = 37ms, Average = 21ms

Results from my laptop

Router: 

Ping statistics for 192.168.1.1:
Packets: Sent = 29906, Received = 29899,Lost = 7 (0% loss),

Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 117ms, Average = 1ms

Google:

Ping statistics for 172.217.4.196:
Packets: Sent = 29906, Received = 29904, Lost = 2 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 16ms, Maximum = 246ms, Average = 23ms

I switched off pc, router and mode. turned back on modem first, router then pc before this. Firmware is updated to most current version. GEO filter and QOS off. Test was ran through the night with no internet usage. I tried running a speed test on PC which got to 960/40 and this did not cause and dropped packet nor any change in response time. I've checked ethernet driver for most current version, and turned off IPv6, and two different low power mode/ energry conservation settings in ethernet driver. I have left all timing of the ping test as per standard.

Questions:

On my PC how am I losing packets between pc and router but not pc and Google which is through the router?

I have also set up a guest wifi network and put my fire tv stick on it with password protection. I am able to ping it from my pc on my wired network. I thought guest and main networks were meant to be isolated?

Wifi speed on 5Ghz drops to about 400-600 down. wifi adapter is next to router. The adapter specs states 1700+ but when I go into adapter settings it only shows speed of 866 I believe. Why is the wifi not even running to 866? Under settings the 5Ghz says 1700+. 2.4Ghz drops to about 80 but under settings states 800? I have an Aorus pro wifi motherboard if that helps.

Sorry if I've missed out anything.

Appreciate all help in advance.