LED Light Show Xmas lights inconsistent

We bought 21 ten foot (12 LED's each) strings of Toyo International Group Light Show LED C9 Christmas lights for the outside of our home. There is a stated 17 set in series limit, so there are about 13 sets on one outlet and 9 on another. The lamps are clear and change colors sequentially as controlled by a module at the beginning of each set.

Almost immediately, upon initial turn on, the first set on the long string had the last half (6) of its lights out. Along the ridgetop were several more instances where 4 or more lights stayed white instead of changing colors like the rest. Otherwise it was a gorgeous sight. You are not supposed to mess with the lamps while it has power, so I shut off the system and my grandson pulled out the first dead LED fitting, replacing it with a spare. That didn't totally fix things, but that lamp did light. He replaced the next two in line, but though the string lit up, the last 4 were white. Now the first lamp in that set lights correctly with all the rest of the sets in harmony, but the next 5 may be white, then 6 don't light, or sometimes #2 through #12 have a barely discernable orange glow. We are too frustrated to crawl way back up on the ridgeline to fool with the groups of white-only lamps. The lamps/holders that my grandson removed look perfectly fine - no discoloration or abnormally bent prongs.

Is this just a matter of reversed male cord plugs? Is it a lamp inserted wrong? The lamp holders have extrusions that theoretically allow them to go in the sockets only one way. The bulbs in their holders have 4 prongs that bend back 150 degrees or so. Could it be just that one or more prongs need flaring out a bit to engage the socket contacts better? Or is there faults in the sealed controller modules?

We went to a lot of work to mount these on our roof. To then find they don't work quite right is aggravating, especially adding in the cost of the sets. The Toyo company doesn't respond to my emails for help, and their instruction sheet is oversimplified, poorly written, and virtually useless.

UPDATE:

I removed the first faulty string that my grandson had worked with from the house, and took it to my workbench. I replaced the #7 LED (from the male plug end) since it was originally the first faulty light of the 12 total in the set. I understand that they are wired in sixes, but am clueless beyond that. Replacing that LED had no effect - LED's #7-#12 stayed white. I then worked my way toward the male plug, and I don't recall the exact configurations, but at some point the only correctly working LED was in position #1. Finally I either replaced the LED or tweaked the 4 wires on #2 and the entire set began working correctly. I put it back on the roof and it is still working fine a week later.

I then removed faulty set number two and took it to my workbench - it also had the last 6 lamps staying white. This time I immediately replaced LED #2, and the entire set worked correctly right off the bat. The other faulty sets are high on the ridgeline and hard to access, so we've elected to wait until they come down post-season to try repairs. Two or three sets have 4 lights in succession that stay white. One set has 6 in a row that change colors correctly but flicker; I suspect this is a case of one LED with one or more of its 4 wires that aren't making good electrical contact in its holder - the hassle is figuring out which one.

I have yet to hear back from Toyo Group, the distributor and the only name on the box. I discovered that Lowe's and others sell what appears to be the same lights under the same names on the same colored boxes, but the manufacturer or distributor is Gemmy. I found them on the internet and wrote them asking for repair guidance. No response yet. Understanding how these in-motion, module-controlled LED sets work would certainly help when they display incorrectly. The boxes nor the instructions identify the manufacturer nor how to associate specific display faults with a specific repair.

If we fix all the glitches when the sets come off the house, we will have the dilemna of haveing to decide whether to trust they will keep working okay next year, or taking all 21 sets back to the store for a refund. If the latter, next year's sets will likely be GE or Phillips. They are a lot more expensive, but appear to have stouter construction and their boxes and instruction sheets seem to fall all over themselves offering help and customer service.