I've used the Foodsaver for well over a decade now, and here are some things I can offer up.
First. the bags just aren't what they were in the past. They are getting thinner, don't hold the seals as well, and many will not reseal the second time (they have become more of a throw away thing, which they aren't supposed to be). And because the bags are thinner, they are more susceptible to puncture in the freezer when getting jostled around.
When sealing raw meat, I make sure to do several things.
First, choose the moist setting (if you have it on your machine). It provides a longer sealing time for when juices/liquids are sucked up into the sealing area.
Second, for something like ground beef, make it a compact ball of meat, and press it down into the bottom of the bag a bit.
Third, make the bag big enough. I think a lot of people worry about wasting the roll of material, and make the bag too small, so the machine doesn't get a good grip at the top. You can also make the bag much too big and waste space, but too small has proved to give me a weaker effect in the past.
Fourth, let the bag seal down completely. Don't interrupt the cycle and self seal (yes this is an option, but not really good to use for freezer items as there will be some air left inside, and is more for baked goods or delicate items).
There is a learning curve with getting the open end of the bag down into the tray in just the right manner to allow full vacuuming. What I am finding since the bags are thinner is that they are not open enough sometimes to allow good suction. So I will crumple the open end of the bag a bit before putting it into the tray and closing the lid. This seems to allow the vacuuming to be more effective and faster.
I do notice that the strength of the motor seems to wane over time (I'm on my second machine, I wore the first one out) and wonder if the newer ones are as strong as in the past.
My guess, if there appears to be ice crystals inside the bag, and the meat was raw going in, is that not all the air came out.
Keep trying while you have the time, and if it doesn't seem right, perhaps ask for an exchange before giving up totally.
Hope you can find something of value in my ramblings!
@ladypfeif