Extraordinary SLOW performance on ReadyNAS NV+

Ive got a problem. Spent 4 days trolling the internet for answers and Ive finally admitted defeat and hope someone on this forum can offer a solution. Sofar, what I have learned from the internet is that a lot of people are getting slow performance from ReadyNAS devices, but very few getting such poor performance as I am getting. Also there are thousands of people offering solutions that are nothing short of guesses. There are very few true experts and those that are are not answering my problem.

The unit is an NV+ (says v3 on the bottom but I now know this is really a v1 - good one Netgear!!)
It has a 4x1T disk X-Raid and has worked just fine for a long time looking after work and family stuff - pics, videos, backups, etc. There is 396G of data on it.

It recently started to go very very slow. Read/write transfer speeds are 327KB/s (KB.... not MB!!). I have a small simple SOHO network for contract work and home duties, Ethernet 100 and Wireless N. All Cat6 cabling and GB switches. The GB router is coming soon.

Initially I suspected the Win7 laptop. Many configuration alterations and tweaks with no improvement caused me to look elsewhere. The following major changes all resulted in NO performance improvement.

1. Use WinXP Pro instead of Win7 (performance on WinXP was much worse)
2. Use NFS shares for Win7 (this is the 327KB/s setting - CIFS shares barely work at all)
3. FTP transfers.
4. Direct cable connection to Win7 computer (no router)
5. Direct cable connection to XP computer (no router)
6. Play with various MTU settings
7. Play with a lot of other settings suggested by "internet experts" (all now returned back to original settings)

Losing all data on the NAS is not really an option. 20 years of family photos and other stuff are in various places - dvds, backup drives, etc., but I would rather not chase this lot up. If I fix this problem I will implement a more secure system.

At present I am recovering the NAS contents, downloading the entire contents, 396G at 327KB/s - this should ONLY take about 14 days :evil:
When I have recovered it all I can do what I want. I sure had better things to do with my time, and not too happy with Netgear at present. The NAS and the drives are quite new and I would not expect hardware failures this soon. The drives are WD and on the compatibility list.

My questions are.
1. If I buy a more recent NAS, say a RN104, can I just plug my existing x-raid array into it and carry on?
2. Any clues about the likely cause of the problem? I am an embedded control engineer and in my field things just don't go slow - they work or they don't, so I am at a loss to think of a failure mode that may cause these symptoms.

This is not such a bad option for me as I get all the new features - GB connectivity and addons that the NV+ has not got. I am prepared to take a chance with Netgear just ONE more time.

One more thing - if I transfer say 5 to 10MB of data and check the error log using Frontview I see about 2500 TCP retransmits, but NO other errors. I am sure this is diagnostic. Any clues?

Also, the SMART check on each of the drives show no indication of any faults, or even any impending faults.

Any help in this matter would, I am sure, prolong my life immeasurably, and receive my gratitude.

cheers, JohnF


Added later after some thought. I have a machine running Ubuntu. Can I hook the disks from the NAS up to this to recover the data, and if so how should I go about it?