I tried firmware ve 1.00 and 1.01B8 on 857. And I have a USB3.0 HDD hub with 2 HDDs(2TB FAT32 & 500GB NTFS) attached to 857.Some issues and experience:
1. DLNA
I used my win7 laptop and ipad2(XBMC) to watch videos from 857's upnp sharing(DLNA). But 857 can find very few files, even lose whole folders. These files can be supported well by win7 Home Group stream media sharing. If you cant see anything in DLNA:DIR857, my experience is: resetting 857 to factory default and reconfig it can be some help. But dont look forward to see all types of the files supported by DLNA till now.
Setup DHCP reserved IP addresses for all devices ON the router. Setup/Networking
Ensure devices are set to auto obtain an IP address.
Enable uPnP and Multi-cast Streaming under Advanced/Networking.
2. Samba
Samba sharing is better than DLNA. I can use my laptop of android2.3/4.0 phone to login to my HDDs as a network neighbor. Login by 857's admin account, I can read/change/delete any files. But when I use my ipad2(5.0 ro 5.11 jailbreaked), apps like xbmc or fileexplorer can not login to 857 by admin account, or guest account with pw. Only guest account with empty pw can let me access. BTW, when mount my HDDs, FAT32 disk's transfering speed can be about 16(write)-32(read)Mbytes/s, but NTFS disk's speed is terrible slow, which is less than half of the FAT32 disk. A little disappointed with IP8000 cpu.
Have you reformatted your disks with a clean format and reloaded files? NTFS is the better format. How are these drives connected? External source or shared out? Any security SW running? Things like that, firewalls, Windows Search and back ground programs can effect file performance. Have you tried using a external network switch between the router and PCs and other wired devices? This eliminates additional router processing which the router is designed to do. Processing will always have some sort of impact on connected devices.
3. Shareport plus
I installed shareport 4.11 on my PC and there's no problem. But the apps on IOS or android are both useless, they just give me authentication errors time after time, whether I use admin or guest account. I think shareport apps are not fully support 857 now. Possible how the router or your devices are set up could be effecting how the apps are working.
4. Operation
Admin interface is unfriendly, any configuration changes(even only change the DMZ IP) force me to reboot the device, and the rebooting time is dreadfully long. And the most important: NO backup file can be import, whether after I reseted the device, or when I try to import a bin file which just generated 5 seconds before. The backup .bin file can be opened by notepad or editplus without problem, but its maker cant verify it and give me a fail response every time. Sounds like user operation of your router is a problem. What browser are you using? I have worked with this router for a while now and don't see any issues on exporting or importing the configuration file. The admin interface is fairly easy. It's the same UI as most of the other DLink routers. You do have the reboot later option and it comes in handy when you have to do a lot of configuration, just save and REBOOT LATER. There are good reason why the reboot takes a minute. It's not that bad. Try a DIR-825 or a 655, you have to reboot after making any changes and you don't get a reboot later option.Try using IE 8 or 9 in compatibility mode. I've used Opera and Safari on my Mac and don't have any issues managing this or any other Dlink router.
From the above, DIR-857's firmware still needs a lot of improvement, hope we can see some progress in next firmware.Maybe dlink should consider to support HDDs' ext3/4 or exfat format. If NTFS processing capability is restricted by the chipset and linux kernel, ext3/4 should have batter performance. However,a "HD Media Router" should not has the 2GB file sizer limitaion of FAT32.
The FW is very stable at this time. There maybe a few items or corner cases where users seem to be experiencing some odd behavior, however over all the FW is good and others are enjoying it. There maybe good reasons why DLink has a limitation on USB drive sizes. So far my WD MyBook 2Tb USB drive is working however I don't use it connected to the router. I get better use when it's connected to my Server PC. Less hassle in this format and works better for me. Having large HDD sizes is nice, however USB still can't hold a candle to IDE or SATA speeds. Specially for streaming and working with large file sizes. If your looking for the next Peta byte size drives to connect to any poor router that has a usb port, then your barking up the wrong tree. You might want to confider your real needs of your set and and devices. There might be better ways of connecting devices and getting good performance out of them. Not trying to discourage you in anyways, just trying to be practical and offer some practical thinking. If you really think there is an issue, and after trying some of the suggestions, guess you should call Dlink customer support and talk to someone about it. Maybe someone can review your router settings using teamviwer with you and go over some items you are concerned about.