My triple turn signal does not seem to work at certain times especially on highways. While parking in my garage, it works just fine. But when I'm driving probably above 30 mph, it doesn't seem to work. Is anyone experiencing similar triple turn signal activation issue?

Do you mean it only blinks once? My experience is more like the opposite, if I try to blink once, the car tends to indicate three times. You have to operate the stalk a bit longer but not too long to avoid the second blink.

With the bimmer, when I move the signal stalk up or down to the point where it does not hold, and the turning signal (blinker) will blink 3 times. I can do this at any speed for left or right. For the EQS, it seems that triple blink turn signal only works under 30 mph. Anything above that speed is a no go. Should I do something different in the EQS to get 3 blinks without having to hold the stalk up or down above 30 mph?

I hadn't paid much attention to this "triple turn signal" before. But I noticed it happening on the highway not long ago, when I wasn't expecting it.
Then, after reading this thread, I tried it while sitting in my garage and it did not work.

I don't know what the "trick" is to make it work. Driving home today at 45, I decided to use it and it worked. Then driving along at 35 mph, it didn't work. So, I'm confused as ever. I tried to look for one of those how to MB videos but could not find one. I don't normally sign anyways, being a BMW driver and all. I just didn't want people to think MB drivers were like BMW drivers . . . hardly ever signal.

How it works is that you slightly push down the signal and release then it indicates three times, if you push down the signal and hold it for a second then release it will then signal once instead of three times, if you push it beyond resistance (like any car) as you know it will keep signaling until you turn the steering wheel to either side or you release it.

I've tried this thing to no avail. I will just be my old self and not signal.

Today, I looked like a nut case signaling left and right at different speeds and different hold down duration. An old lady drove pass me and gave me the funny look.

There must be an issue with the signal stalk in your car then. Flicking the stalk (not all the way to hold position) at any speed triggers the three blinks on my car, same as all previous MB's.