Dell Monitor blinking on and off with Macbook Pro

I just discovered that when I set the monitor at 30 Hz everything works flawless but when I unplug the MacBook from the dock or restart it all of the Monitor settings are reset then flickering comes back because the monitor set itself to 60 Hz

It's not just Macs - I have both Mac & PCs. At work, I use a gaming/engineering laptop by Elucktronics running Windows 10 using the CalDigit dock and have the exact same issue. After my research, given the variety of machines and platforms with this issue, I'm confident this isn't a computer issue (PC/Mac). I've tried numerous monitors and cables (display port/HDMI). I swapped the display port and HDMI cables between monitors and the problem follows the port. I swapped docks and the new dock worked fine for two weeks, then started having the same issue. Interestingly, I then swapped back to my original dock and it worked fine for about a week, then started back to flashing mode. Yesterday, it went into this mode, I was so frustrated I put the machine to sleep, took care of a few other things, came back 20 minutes later, and it worked fine for the rest of the day -- All of that suggests it's not a monitor issue or a driver issue (which are all up to date BTW). Clearly, this is a dock issue that CalDigit needs to address.

muslebard wrote:

As an update, I tried something different:

With the Macbook open, I unplugged the monitor from the back of the dock station (CalDigit) and plugged it back in, and that gave me a constant image.

I thought this was great and that I had discovered a workaround. Unfortunately, the next time I tried this, it didn't work. Now I can't turn the monitor on AT ALL without blinking. Every time I try unplugging from the back of the CalDigit, it connects with blinking. And every time I try what I have previously (the original post) the screen connects with blinking.

I really hope there is some solution!

Thanks.

I am having the same issue with a different model I just purchased today. I apologize I do not have a solution. I am relearning things the hard way when working with macOS hardware and non-Apple sanctioned monitors. Either the screen is blinking off and on, or the monitor is blank and displaying the message "The current input timing is not supported by the monitor display. Please change your input timing to 2560x1440, 60Hz or any other monitor listed timing as per the monitor specifications." This message appears while the display is set to that exact setting and when I change to other input timing settings that are supported. Other times, the Macbook does not detect that a cable is connected at all, but just as the monitor reaches the 4 minute point where it times out to power down due to not detecting itself being connected to the Macbook, the monitor suddenly cuts on displaying a blank display that I can somehow use, but of course it goes into another cycle of failure momentarily. I tried the U2720Q last year and had the same issues, swallowed my pride, and returned the display. I will need to do the same with this one.

I have the same issue; with this configuration: MBP M1 connected to the Caldigit TS3+ and dock connected with display port to the Dell S2721QS. I bought this monitor a few days ago and this is so annoying :( when the MacBook goes to sleep or restart or any setup of monitor change; flickering/blinking starts again. I don't know what I must to do!