I installed insulated laminate flooring in my living room/office 5 months ago & am now experiencing crackling noices as I walk across the floor

What type of foam barrier did you install under the laminate?

The insulation came bonded on the laminate flooring & I was told I didn't have to apply any other product to the cement floor.

Crackle sound like velcro pulling apart? With the foam adhered to each plank, you would still need a moisture barrier under the installation. I gather from your second post that you only snapped the floor together over the bare concrete?

The crackle sound you hear is either old adhesive residue on the slab that the plank sticks to momentarily then releases if there was a prior glued down floor that was removed or it's the foam has released from the plank, possibly from slab vapor emissions gathering beneath, and you hear the sound of the pad adhering/releasing over and over.

I bought some inexpensive snap flooring at Costco. Sounds similar to what golf bought. If the floor is not flat or properly shimmed the locking groove will flex and give a cracking sounds.

OK so do I have to take the floor up & install a vapor barrier on the clean floor that was covered by carpet in the past?

Reread your installation instructions. I think the attached foam qualifies as their acceptable barrier. What brand did you buy?

I'm sorry I don't know, I bought the product from Lowe's about 6 months ago. I have some extra pieces in the garage but they don't have a name on them. I'll have to make a trip to the store to find out.

Take a piece to the store with you to help identify. Lowe's only sells 4-5 brands of laminate