Synergistic LED's How long do they last ???

Gundam91, Most audio nuts (like me) will keep them powered on all the time. They take a few days (3-4) to get back to there best after being unplugged.
That being said however, Ted from Synergistic is recomending to unplug them for 12 hours a month to allow them to recharge.

But if your gone for a week, I would probably unplug them.

I had two of these rascals burn out in rapid succession. Don't know what I did, but I think it was related to a broken miniplug extension cable. Anyway, you can replace the LEDs by stripping the shrink wrap off, soldering in a new LED, and re-shrinkwrapping. I replaced mine with red, but I think I'll need to bo back to the stock blue so one day I can sell the cables (with full disclosure, of course). If anyone knows what LED is stock, please let me know.

Somewhere above, Ozzy says that the LEDs are the active shielding. I think this is not the case. The LED is powered by the active shielding circiut, but I found 24V in the circuit even with the LED removed.

Der,
Replacing the LED's yourself can have a significant negative impact on the performance of Active Shielding. This is due to the fact the LED's are tied to resistors which not only load the Active Shielding circuit so the MPC does not burn out, but they (resistors, and led) have a direct impact on the sound of the cable when Active Shielding is turned "on"; the differences between LED's and different resistor types can spell the difference between great sound and hard and bright sound.

It is always best to have any such repairs performed at the factory.

Yours in music,
Ted Denney III

Ted, in that case I am glad I asked about the LED. I'm reluctant to ship the cables back for a repair involving such simple and cheap stock parts when I can instead do it myself, save a few bucks on shipping, have almost zero system down-time, and also derive such satisfaction from being self-reliant.

But I don't find any markings on the LED to indicate just what it is, so I still hold out hope that you will tell me or otherwise enable me to do it at home. Please??

May I suggest simply phoning SR and explain your request to Eliott. They'll possibly sell you a pack of LED's at cost + a few bucks shipping. You may even get the OEM heat shrink too. However they'll not likely honor any existing warranties if you do a DIY repair.
These guys are among the best in the business to deal with in my experiences, very accomodating. Meeting Ted personally at Mike Holm's shop, when he demo'd his new Teslas, was an enjoyably memorable occasion indeed.