Although packet signing enhances the security of SMB connections by preventing man-in-the-middle attacks, it can greatly degrade performance in Adobe Premiere environments. Adobe Premiere requires both low-latency and high-performance which is affected by using SMB packet signing.
With SMB packet signing on, each packet is accompanied by a digital signature, allowing the client system to verify that the data has not been altered during transmission however at the expense of low latent operation of the video editor.
Where possible, it’s advisable to conduct these workflows on private, secure networks and disable packet signing on the macOS client.
More information from Apple:
https://support.apple.com/en-us/101442
To turn off SMB signing on macOS, add the following line to /etc/nsmb.conf:
signing_required=no
Save, then unmount and re-mount the shares to take effect
Follow the below to apply the fix for CVE-2016-2114 (server signing) and force the NAS to enable server signing exclusively. It is disabled by default. By enabling, the SMB connections are forced to be signed. When disabled, signing depends on the client.