SD-Wan Hub-to-Spoke Windows Explorer file copy speeds abysmal

[from_afar]

I'm getting terrible results in Windows file sharing on my Hub and Single Spoke setup. Speed test shows ~230Mbps down/200Mbps up, but when I go to copy a file from a Windows 22 server on the Hub to a Win 10 machine on the spoke, the file copy speed hangs at about 1-3MB/s, maxing out at 4. The ethernet interface show 1GB speed so I'm not sure why the performance is so bad. 

Also using Umbrella if that matters. 

Latency and Loss all seem reasonable so don't think it's that:

Thanks for any ideas. 

[alemabrahao]

Do you have threat protection enabled? Do you have any traffic shaping rules configured?

[from_afar]

Sorry for the delayed response. 

Yes, we are using Umbrella but I tried disabling all of the protection for this test and it didn't make any difference. 

No traffic shaping whatsoever. 

[from_afar]

I tried disabling AMP and Umbrella on the spoke MX68, but am still getting the same speeds. Any idea where else I could look for a culprit? Speed test shows 120Mbps down and 26Mbps up. Copying a file in either direction is limited to 3Mbps, sometimes will jump to 5Mbps for a split second when copying to the server, but never more than that. Average is 3Mbps.

[cmr]

What MX devices are at each site?

What firmware version(s) are they running?

What are the two line speeds (up and down)? 

We run a decent sized SD-WAN and file copy speed is close to wire speed, but mainly from 2016/2019 servers as opposed to 2022.

[from_afar]

Thanks for the reply. 
Yes, we are using Umbrellas threat protection services. 
we have 1gig connections at both locations. MS-125-48, MS-425, MX-68 at spoke and MX-95 at hub. The hub is connected via spf+ 10gig between and 40gig to the host where the servers live. 

[cmr]

Do you have a large MTU set on the server (jumbo frames etc.) or a very small one on the MXs?

[from_afar]

Thanks for the reply. 

I have not made any changes to MTU so they are all default (automatic). Testing on the server itself, it seems everything is set to 1500 

ping www.meraki.com -l 1472 -f

Pinging www.meraki.com [18.161.21.100] with 1472 bytes of data:
Reply from 18.161.21.100: bytes=1472 time=5ms TTL=247

 On the Hub/Lan, I get file copy speeds upwards of 1.5GBits/sec. All of the speeds are set to auto; VMware sees the 10Gb speeds, though: