So if you want to disable the firewall permanently, you should be able to do it by following this guide if disabled in the control panel it should stay off. We’ve had to do that on rare occasion with systems at work.
If you want to place a hardware firewall outside your devices to then keep them safe, you can do that, depending on your network setup and needs. I’d need to know more about your setup to make any recommendations.
However others are correct: You have an issue in that throughput just isn’t going to be that good. 1 gig ethernet caps out at 125MB/sec absolute max and when you take overhead into account 100MB/sec is about the best you ever see. SATA SSDs can pull 550MB/sec, nVME SSDs can pull as much as 7500MB/sec.
That aside, NICs have pretty high ISR overhead, which can interfere with realtime audio.
The best solution is to do something where you edit the data locally and then sync it to a network server. You can do that manually, or you can get software to do nightly syncs when you are not using the systems.
If you insist on doing it directly off a network file server, then you need to upgrade your gear to work better with that. What you’ll want is several things:
A file server with SSDs, and good caching. Since you are going to be doing not just random access, but multi-client random access you are going to want something solid that can handle that. Just how solid depends on how hard you are hitting it, I’d have to know more to make a specific recommendation. In general I’m going to recommend a NetApp AFF but I can say with certainty you aren’t going to get one because of the cost (6 figures). A good server running Windows is probably a more economical choice but still expensive.
A server that supports SMB 3 and SMB Multichannel. A Windows server will do so, NetApp can too. Ideally, you’d want SMB Direct (RDMA) as well, that is pretty much Windows server only.
10 or 25gig server NICs that support RMDA and other offloads, including in your client computers. I recommend Intel E810-XXVDA2 adapters, they’ll do 25gig and everything you need. These are not just for the speed, but for the features.
A network that supports iWARP, which is RDMA over TCP. You need a switch that can handle the flow control settings and such. In theory it might work fine over an unmanaged 10gig switch, but I’ve never tried it and I’d want to have a managed switch that is properly configured for it.
Do all that, and you can get near native performance from network storage. There is still some overhead, but much, much less. However it can be costly, and complex. SMB Multichannel has some complexity to setting it up, SMB Direct has even more.
One thing you can try right now is go to your Synology, and see if it supports SMB 3, and if it does, turn it on if it isn’t. A lot of NAS devices default to SMB 2, or 1, and those don’t perform as well.