The last two smokes I have had to turn it off and then restart it for it to start up.  Both times it was a clean smoker and both times it would go through the numbers, but the temperature would never get above the ambient temperature.  The fan is running, but cool air and no smoke is coming out.  Once I turn it off and then back on it fires up right away.  The first time after it fired up the temperature ran hot for a while which I suspect was excess pellets was in the burn pot.  The second time I watched it closer and turned it off quicker. 

I did notice the auger was loud, but this may be normal.  I usually turn it on and then do something else until it is ready to cook on.  I have a new control board.  I am suspecting the hot rod, but I wanted to check here first.

I would empty the fire pot and the pellet hopper and turn on the unit.  If you do not see the hot rod glow, that may be an indication that it needs to be replaced.

 "Clean smoker".  Was the auger devoid of pellets? If it was, the time it takes to deliver enough pellets to start and maintain a fire wouldn't be long enough..Simply put, the igniter would have run thru its cycle   

 by the time enough pellets got into the pot.

 Timing. At start-up, the auger and igniter work in unison. Have you ever WATCHED THE FIREPOT @ START-UP to confirm this?

 If pellet delivery is the problem it should also have an affect high temperatures.

For some reason, once and a while, my DC does the same thing. Now, when I fire it up, I stick around until I see smoke. 

 "Clean smoker".  Was the auger devoid of pellets? If it was, the time it takes to deliver enough pellets to start and maintain a fire wouldn't be long enough..Simply put, the igniter would have run thru its cycle   

 by the time enough pellets got into the pot.

 Timing. At start-up, the auger and igniter work in unison. Have you ever WATCHED THE FIREPOT @ START-UP to confirm this?

 If pellet delivery is the problem it should also have an affect high temperatures.

The auger still has pellets.  I only vacuum the firepot.

I will need to watch the firepot to check on the ignitor.

Look at the fire pot before you vacuum. Are there fresh pellets in there? Some of the algorithms for the pits will pump a small handful of pellets into the firepot after the shut down procedure is complete as is done with RT grills.  Those are there for two reasons:
1. to make sure that the smoldering pellets in the end of the auger tube are expelled at the end of the shut down cycle.
2. to make tinder for the starter to work on when you start up again.
So if you suction it out after every cook (not really nec. with most of the units), you should put back a little pile of pellets around the hot rod for the next startup.
Also, when the fan goes off, and the auger turns a few times at the end, those pellets also help to suffocate those few embers that remain in the ash. Not sure your pit works the same way. Easy to find out by getting the grates, pan and deflector out before the shut down is complete. If the fan goes off, and then the auger starts up and delivers a little pile of pellets, ==there you have it. Would like to know if that is a good solution for you. 

On GMG web pages, I found the following;
1. Vacuuming the unit every 2 or 3 bags of pellets but no comment on vacuuming the firepot after every cook.  The fan system is very efficient in keeping the ashes in the pot low enough as to not block the air flow and fire output. Saw no comment on the mechanics of the shut down.

Just my experience here, but I had better luck with my little DC after cleaning the pot, to add about a half cup of pellets to the pot before reassembling it.  This would virtually guarantee a first time start after a cleaning.

Just my 2 cents.

I do not vacuum out my fireport after each use.  How this appears that way is I cleaned it after several smokes and prior to a long/greasy smoke (first smoke).  I then cleaned it after the long/greasy smoke (second smoke).  I usually go 3 to 5 smokes between cleaning it.

I have not noticed any unburned pellets when I vacuum the firepot, but I will double check it.

I have had something similar happen. It would cycle through but no temp change. Turned out the auger was stuck. So bad that it was difficult to get out. I just tapped around the auger housing on the inside of the grill would turn the on/off switch on to get it move a little bit and finally got it pulled out. I blamed the long maple pellets. Some were 2"-3". Never had it happen before just when I started using the new bag of pellets. I got a bucket and hammer and just started to pound them down in like 5 lb increments. 

I have had something similar happen. It would cycle through but no temp change. Turned out the auger was stuck. So bad that it was difficult to get out. I just tapped around the auger housing on the inside of the grill would turn the on/off switch on to get it move a little bit and finally got it pulled out. I blamed the long maple pellets. Some were 2"-3". Never had it happen before just when I started using the new bag of pellets. I got a bucket and hammer and just started to pound them down in like 5 lb increments.

You may be on to something.  A while back I bought some pellets from Sam's Club.  I used them a few times, but they jammed my auger.  I quit using them and used them only in my smoke tube.  I remember putting them in again being I was low on pellets and they was the easiest to get.  I keep them in a large container where my other pellets are stored in a cabinet.  The noise my auger made the last time was similar to the noise when the pellets would jam up my auger.

I have had something similar happen. It would cycle through but no temp change. Turned out the auger was stuck. So bad that it was difficult to get out. I just tapped around the auger housing on the inside of the grill would turn the on/off switch on to get it move a little bit and finally got it pulled out. I blamed the long maple pellets. Some were 2"-3". Never had it happen before just when I started using the new bag of pellets. I got a bucket and hammer and just started to pound them down in like 5 lb increments.

You may be on to something.  A while back I bought some pellets from Sam's Club.  I used them a few times, but they jammed my auger.  I quit using them and used them only in my smoke tube.  I remember putting them in again being I was low on pellets and they was the easiest to get.  I keep them in a large container where my other pellets are stored in a cabinet.  The noise my auger made the last time was similar to the noise when the pellets would jam up my auger.

You may be on to something with the pellets and jamming. Myself and another member made a bulk purchase of pellets a couple years back, and I remember him mentioning something about his auger jamming on his GMG units.  Last year I put those pellets in my little GMG and had the auger jam and shear the cotter key.  That was something I don’t want to repeat again anytime soon.   The bulk pellets work fine in the Memphis and Louisiana. I have returned to the PitBoss pellets which is at both our local big box lumber stores(Lowes and Menards) and possibly Wally World.

Pellet composition and or compression hardness? Why do they jam? Excellent question..

Problem resolved itself by changing pellets.   

now you guys have me thinking...i have had some issues with my MAK lately including slow up to temp and shutting down mid cook.  I vaguely recall some long pellets and some clunking of the auger.  once it warms up i will have to take a look at it as i may have had the same problem you are each suggesting

My go to brand is Lumberjack and AFAIK I have not had any issues with them.  I bought the Sam's Club brand when I was low on LJ.  I have also used Pit Boss, but mainly for hot grilling.  Being I needed space I mixed my Pit Boss with the Sam's Club brand and figured they would work when I needed them.  I have one of the large charcoal containers that they are in.  I will go back to only using the mixture in my smoke tube and stick with LJ.

I am 100% Lumberjack competition blend. I ran out and had to mix some cherry, hickory, and maple together of some bags I had. I have had no issues with the competition blend running through my DB. I just got 400 lbs more the other day.