I reply to old message, but perhaps still relevant:

The 2.1mm and 2.5mm specs refer to the size of the hole in the plug, likewise to the size of the pin in the dc jack on the Gridseed.

I use a 5.5mm x 2.1mm plug for mine. 
The fact that a 2.5mm plug has worked for some miners is because .4mm is a tiny difference, and the plug with the larger hole will still make contact.  But the snugger fit is better.

Radio Shack Connector "M" is 5.5mm x 2.1mm.
They have another connector ("K" I think) that is 5.0mm (outside diameter of barrel) x 2.1mm.  This one will work, also.

If you dont solder, here is an Amazon search arg for such plugs with screw terminals.  They work nicely, and are stupid cheap:

niceEshop 10 Pcs 2.1x5.5mm Male Jack DC Power Adapter for CCTV Camera

Not knowing anything specific about GPU mining does not stop me from offereing an answer based on a life of electron herding:

Swap the two cards into the opposite sockets, then make logical conclusions based on the results.  With any intermittent condition, after you intervene it may take a few days before the problem shows up again at all.

If your cards are connected through risers, you may need a second step of leaving the cards connected to the same sockets as you just swapped them to, but this time swapping the risers themselves. 

I always like having things in pairs because it makes circuit-level diagnosis easier.

YES, you are mining correctly.

When you start, it takes at least one hourly cycle before you see any stats.  I see stats for you, so I daresay you have seen these stats as well, at this page:

http://www.clevermining.com/users/1BV29LFCT7KuLDsAp9DbSf4kK8ANw7xDvT

Maybe you dont need any of this info I am going to provide.  Some of it is unique to CleverMining, so I will tell you what I have learned:

Stats are true at the top of the hour, but they are not updated on your stats page until some minutes later.  Varies.

Big green circle says:
18.6 KH/s
This is your effective hash rate.  The stats suggest that you started mining at CM before 11:00 UTC, because you have some stats.  If your mining hardware is hashing at a faster rate than 18.6 KHps...well, let's say you are hashing at 72 KHps:  I would guess that you have been mining for about 15 minutes.  Rejects and such also impact the hashrate, and it seems to even reflect "pool luck".

0.00000207 BTC  immature
0.00000013 BTC  unexchanged
0.00000000 BTC  ready for payout
0.00000220 BTC  total expected

Notice that Immature, Unexchanged, and Ready for payout add up to Total Expected.  Also, Total Profits:  .00000220 is the same figure as Total Expected.  So you should interpret Total Profits as "Total Expected Profits Dont Try To Spend Them Yet."

Immature, I believe, means not yet confirmed by subsequent mining work.

Unexchanged means confirmed, but not yet converted to Bitcoin.  That exchange will happen right before (or right after?) 0:00 UTC.  When your earnings are exchanged, their number moves from the Unexchanged cell to the Ready for payout cell.

If your Ready for payout is >= .01 BTC at 0:30 UTC, CM will pay your total Ready for payout to your wallet.  Each and every day.
If your Ready for payout has not reached .01 BTC by Sunday, CM will pay your entire (small) Ready for payout to your wallet.  (I think this payout happens at 0:00 UTC Sunday morning).

In each case, your Ready for payout will become 0.00000000, and of course Total Expected will be reduced by the amount of the payout.

By now, with my typing so slowly, you should see figures for another hour's work.
Good luck.

I am getting Website is Offline when I try to hit my CleverMining stats page.  The other day, somebody provided this URL to be used to find out, in this situation, if CloudFlare is the problem:

https://www.cloudflare.com/system-status

That site lists status only through Apr 27, and today is Apr 28, so I have to ask:  Anybody else unable to hit CM stats?

Back up at 13:59 EDT.

Jordo!  Thanks 10^6.
I was getting the answer, but knew nothing about the cf_clearance cookie.
You take a huge risk putting yourself in a support position

I neednt link you now, your text is exactly what I read.  I did not reach the conclusion that you did about the crawlers being whitelisted, thanks for helping me think! 

As to "kind of a pain", well, it would be worth it so I could get some sleep, I'm plain stupid about having to check every hour and enter data into a spreadsheet.  Auto-reading from CM is the only missing link.  I'm databasing the exchange rates of 5 different coins once every five minutes, making graphs, all automatically.

Hey, I hear you.

Let me say that I worked as an electronics technician for 17 years, and no matter how smart you are about diagnosing, you are also lucky any time you get it right.  (Like putting in golf...)

I control some lights in my house using X10 controllers.  Lightning struck a tree outside my house.  Afterwards, I could remotely turn the kitchen light off (which is what I always want to do), but I could not turn it on.  I replaced the switch module, and the receiver, and used a different hand unit.  Tried different house and device codes, no joy.  The one night, suddenly, the light turned ITSELF on!  I tried my hand unit right away, and sure enough, I could now turn the light on, and I could turn it off.  But it continues to turn itself on from time to time, several times a day.

I am having the same problem in trying to "data scrape" as you call it.  I read on the CloudFlare site that their protection does not prevent web crawlers from scanning the site (so I am confident we can find a way to do it), and I'm thinking what I will try next is to write code to accept their cookie(s).  Of course, my guess is worthless until I have it running.

What I unsuccessfully tried in php was to file_get_contents, then do a javascript setTimeout of 10 seconds, after which I do a window.location.reload.  

I had a day when all my gridseeds shut down at once.  I did "this and that" and they finally started up.
I left the house, came back.  Again they all shut down.

Long story short, I finally concluded that plugging my phone into a port on the front of the computer that runs my mining software was what caused it.

Pardon me for not qualifying what "this and that" includes,  nor detailing what mining software I am using and etc.  I tied a knot in the cable that I was using to charge my phone so I would recognize it and never use it again (but I kept it in case I wanted to prove it was the culprit).

...I use a USB mapping utility called UsbTreeView, and on its diagram the port where my phone was plugged in, it showed a yellow "i" indicating a problem. 

I am not suggesting that your telephone is causing your problem, but rather I am encouraging you to maybe look elsewhere besides the gridseeds and power supply, as I had to do.

OR, I'm willing to make a joke without hiding behind an emoticon 

My intent was to commend Terk by implying he has powers beyond reason.

On page 187 of this thread, there was a good discussion of fake vs genuine rejects.  These two messages seem to be correct:

Xenocyde  April 16, 2014, 02:32:08 PM
byt411      April 16, 2014, 02:37:11 PM

Another reply you received here, about comparing the red plot vs the blue on the Rejected Percentage chart, very good.

I myself count the fish in the boat, and dont worry if some fish got away...

Terk!

What a great day for Clevermining.  I am too excited to go to sleep, so I looked at the About the Pool page.  I see LAST 24 HOURS STATS, and LAST 30 DAYS STATS.  When will you implement NEXT 30 DAYS STATS?

Doge Tips Address:  DSJLWtjYat5vunYSXWGsQs5CXxFewAv6Mi

Rising USD/BTC can be exciting, but it has no bearing on the BTC/Day/MH figure on the stats page, and that figure has moved from its usual .004 to like .00623...

Perhaps I could rival Terk's technical ability, but...I know I could not handle the jealous screamings of "Give me my penny!"

Will this device run on bitminter client?