Amp keeps shutting off

I have the Schiit Vidar powering two 98db 1w/1m speakers. This thing will turn into fault mode so quick once turned up. Only using 4-10 watts per channel, it will turn off after 20min with a box fan blowing on it. I took the cover of the amp off, which I didn't want to do, and that didn't help at all (again with a box fan blowing on it). Once using anything above the 30 watt per channel range, the thing will last 1 minute before shutting off (although that 1 minute sounds really good). The amp is rated for 100w RMS per channel into 8 ohms. I'm not expecting it to actually sustain that rated power, but come on. Why isn't it at least sustaining 20 or 30 or even 10? Am I doing something wrong? Or am I out of luck?
Double check the speaker wiring/connections. If good, try the Vidar on another known good speaker in an attempt to replicate the fault.
I have read the Schiit Vidars have had some quality issues.  Or perhaps it was their Aegir models.  One of them supposedly had a lot of malfunctions.

This thing will turn into fault mode so quick once turned up.

Sounds like the bias has drifted, and the thermal cutout is activating. Send it back for service with your explanation details of it reaching cutout stage.

Cheers George
I agree 100%, with advice from georgehifi. Send it back for service.
A blonde got stuck in her cute Mercedes Benz and cannot start it.
Another blonde pulls over to help friend and asking if she's wiped out headlights, bumper and dashboard.
-- Yes I did
-- I don't know what's the problem then sorry!
That makes ZERO sense, czarivey

Check the cabling and back to the factory..

Try without playing music.  If it happens then, turn off, disconnect inputs.

If your amp is DC coupled, an upstream DC bias will cause these issues as well.
How are you measuring the amp's output? 30 watts continuous using a 100wpc amp is going to create a heavy thermal load. You'll want to have the amp looked at but you might just be driving the poor thing too hard?  
From your Owner’s Manual:

Okay, so you have a flashing light. Deep breath. We’ll get this taken care of shortly.
When the Vidar’s front light flashes during operation (and the amp mutes), or if it never stops flashing after you turn on the amp, there’s a problem, or fault. There are three kinds of faults:
1. Over-temperature. The heatsinks are too hot, and Vidar has shut down to protect its output. If the amp is very hot, turn it off, wait a while for it to cool down, and try turning it on again.
2. Over-current. If Vidar is connected to very low-impedance speakers (2 ohms in stereo, or
4 ohms in mono), playing very loud music can cause an over-current condition. Simply turn the amp off and on again to clear this fault.
Alternately, Vidar may shut off from over-current if the speaker cables are shorted. To trouble- shoot this, turn off the amp, disconnect the speaker cables from the amp, and turn it back on again. If it comes back on, there may be a short in your speaker cables (or your speakers). Examine your connections to ensure there are no stray wires or shorts. Once those have been fixed, you can reconnect the speakers and play music again.
3. High DC offset. Vidar is a DC-coupled amp. Its microprocessor monitors DC levels at the output and adjusts it down to zero. However, it may not be able to correct for high DC from your source (such as a preamp). To clear this fault, turn off the amp, disconnect the RCA cables or XLR cable from the amp, and turn it back on again. If the amp turns on normally, then there may be high DC on the output of your source. Have the source inspected and repaired.

Had an issue with a Primare amp randomly going into fault shut down, couldn’t figure it out. Manufacturer rep was very helpful, suggested it could be DC in the AC (from other devices leaking into home AC). That was confirmed by torroid transformer hum. Maybe that’s your situation?

Power off and on reset, for awhile. Got a DC filter from Emotive (only such filter i found). Surprised that other filter devices didn't filter out stray DC.
I am going to say this as nice as i can but a lot of today's so called high efficiency designs have severe impedance dips in the bass and it is this reason that i believe that the amp is shutting off because low power consumption small amps do not have the current to tackle the low impedance. Try a vintage beast amp at least twenty years old and see what happens but my guess is that one like that will drive your speakers beautifully.

After trying search all posts to find what speakers the OP has, I believe it’s the speakers, causing amp shutdown.
As every post the OP does says nothing about what speakers he has, mentions models of everything else, the only thing said by the OP about the speakers he has is that they are

" My speakers take 200w continuous with peaks to 800w or 1000w"

Something just don’t smell right here.

Cheers George
The Klipsch Epic CF 2. It’s a bright set of speakers that just need to be tamed. The spec sheet says as I wrote, 200w continuous, 800w peak. The Vidar has smoothed them out nicely, although I still have improvements to make. The speakers have never caused an amp to shutdown as the Vidar has in their 25 years of use. I don’t expect that to randomly change.
Contact Schiit. Your speakers are easy to drive and shouldn't be causing your amp to shut down. You're just going to get guesses here.
oedstrom11 OP

The Klipsch Epic CF 2.
OK easy as pie to drive, go way back to my first post and do what I said.

Cheers George
I had a Schiit Vidar used as a monoblock go into protection mode when driving a Magnepan 1.7i speaker. Granted I was playing Jeff Beck loud. Still there is not enough headroom on that amp. Long since sold the Vidars. They were ultimately replaced by a pair of Bryston 28B3 monoblocks. No issues. Plenty of power and headroom. Contact Schiit for service. 

I had a Schiit Vidar used as a monoblock

If he has stereo amps bridged into monoblocks, then there’s the answer.
Don’t know how many times I’ve said this to the Odyssey monoblock crew, a bridged stereo amp is worse in all amplifier specifications (except in 8ohm wattage), they basically become a PA amplifier and can’t handle low impedance like they could when they were stereo.

oedstrom11 OP
Make them stereo again and use one only to see it turns off, my bet is it won’t.
As any stereo amp bridged into mono will not handle lower impedances as well as the same amp left in stereo, they will become unstable when bridged into lower impedances.

If you have 2 sets of speaker binding posts then you could use both amps in stereo still, but vertically or horizontally bi-amp instead, I prefer vertically with exact same amps as the whole power supply is used for one bass drivers transients, where it’s needed.
If only 1 set of terminals you can’t do it without internal surgery on the speaker and another set of binding posts

Cheers George
I had a similar issue with an Aegir using efficient speakers, and they sent me another one that also shut off weirdly (not as frequent as the first, but still)...sent it back. Could have been triggered by my "stacking" REL sub cables (2) on the outputs along with the main speaker load (RELs supposedly add a very high impedance load so they should be transparent to the amp), but that's never been an issue with any other SS or tube amp I've used this way...oh well. Send the Vidar back as the Schiit folks won't mind. 
If you can change the speakers cables do so I think they’re shorten 
try to connect only one speaker to the back of the amp and play
just take one cable out and viceversa 
im 💯 sure is shorten