Nad 326bee popping sound?

www.eserviceinfo.com would be one suggestion. good luck. it is in PDF format. good luck.

Hello. Slapping and it working is a tail sign that there is a loose connection, bad solder point, loose wire. When a circuit board gets hot, solder joints separate and an opening occurs in the circuit. Open it up and get a visual. Look for cold solder joint, make sure all the connectors are secure. Good Luck

The protection only should come on, when the power amplifier has to give more current than it can deliver. (electronic fuse)
If in the music is a lot of subsonic, sound, so low you can't hear and your speakers can't produce, this could cause the problem. Normal CD players will cut of all frequencies beneath 20 Hz, but it could be your PC is giving everything from 1 Hz and above.
I would certainly try to play some music over a CD player and check if that would solve your problem. Not sure if that works, what you could do to suppress the sub sonic in the computer music.

You need only look inside and follow your nose....The smell will lead you the faulty party, probably in the power supply. Just a power surge problem or something that's been going giving up the ghost.

Generally speaking, an amp attempts to protect itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'naked'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced and competent hands-on tech.

Check for loose speaker connections at the speaker as a root cause for ntermittent shutdown.

http://nadelectronics.com/products/hifi-amplifiers/C-326BEE-Stereo-Integrated-Amplifier

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The surge could have taken out the power transformer.

Hi there,
I'm also a Nad fan. I find this pretty odd that you should loose two in such a short space of time. The cutting out is due to the "protection circuit". I would be inclined to get your speakers checked out as if they are faulty or not "matched" to the amp, it will trigger the amp to "protect itself" and shut off.

I, too, have the 3150 and have experienced problems with it. With me the INPUT knob is touchy and needs micro turns sometimes to get both channels to come through. Also, it sounds like the pots are dirty as I get a scratchy sound while adjusting the knob. I have been told that these units are great middle of the road audiophile units. Actually, for the price of a used unit you can't do better. I just had an NAD 2400 THX amp delivered today and am using the 3150 as a preamp. My girlfriend is not feeling well and sleeping in the bedroom, though, and I can't listen to it :( The few minutes I heard of Steely Dan's Cousin Dupree made me bout **** myself (until I got the dirty looks). Sorry I wasn't more help! Goooooo NAD!

It is most probably a dirty speaker protection relay. gently tap the relay(the one that engages shortly after turning the amp on) when the fault is occurring and see audio returns. This should ascertain the problem. Replace it if it is a sealed type, or if it has a "lid" you can get off, burnish the contacts with a white business card, and give it a spray with contact cleaner/lubricant. Good luck and a "fixYa" rating would be great for my profile :)

I have the same problem which started about a month ago and seems to be getting worse. I also noticed today, that 1 channel is significantly louder than the other - fault in the pre-amp stage, as feeding the power stage directly gives balanced, albeit extremely loud sound! Looking on eBay, I found someone else selling an amp with both problems. It would nice to think that NAD would acknowledge a design flaw, and fix for free, but my amp is 5 year old.