An AMPs is a great suggestion but ...... the chips should work.
First how often do you open the door?
More than once and hour is wayyyyyyy too much. An electric is made to never open the door. when you open the door you let the smoke out and cause the heater to run excessively to return the unit to its setting. An Electric recovers heat slowly, I have read somewhere that each time you open the box it add 15 mins to regenerate the heat loss. I find that slightly excessive but even it its 10 mins. if you only open the door once and hour on a 12 hour smoke you've added 2 hours to your cooking time. PLUS you are letting moisture escape. You don't need to mope, spritz, or sauce with an electric. If you keep the doors shut the moisture stays inside where your meats appreciate it.
So all the smoke you didn't get, are the chips burned or unburned after the smoke?
If you are seeing unburnt, you are not achieving a clean burn, if its all burnt you are achieving combustion which means you are getting too much air and need to regulate the vent. The vent is an never ending discussion here on the boards. If the vent is completely open you will use more chips, closed less, its best in the middle after the indication you are getting good smoke.
What flavor wood are you using?
There different types of woods which impart stronger and weaker or milder strengths of flavor. Usually classified as hard and soft smokes depending upon the meats.
What is the position of your vents?
This is a long discussion. I use full open to start then cut back to about 1/2. In the old days there was NO vents, I like the vent idea, makes it much easier yto keep from over smoking.
Are you starting your MES at 275 to heat the box then reducing to the cooking temperature?
Remember this is electric, you are heating chips thru two layers of steel to get to smolder. The heating abilities are much the same as an electric range as compared to a gas. Gas is instantaneous but hard to maintain accurate temps., whereas electric is slow but very accurate. It doesn't happen in 10 mins. Set it high, walk away, check in 30 mins., reduce the boxes temp to your cooking temp, and reduce the vent to 1/2. You should see much smoke before you regulate it, then just a little afterwards. If you see the smoke, it ain't flavoring.
All or any of these can be a problem for smoke.
My biggest problem was in the beginning, I was a peeper. I could not leave that door closed. An electric is not the same as a fire breather and has different rules to use. Although the Chinese manual doesn't help too much...LOL
PS:: One more thing too many chips can hurt your smoking ability. If they are not cleanly burned and you add more looking for more smoke, the new chip can't get to the steel plate to get hot enough to start the smoldering process.
I sure hope you get it figured out. I have worn out three electric smokers prior to my MES30, and I really like their convenience and economy. Its like the plug and play of smokers...LOL