U3818DW, chime noise, MacBook Pro

With all due respect, but the testing protocol of the monitor manufacturer may be flawed.

I'm on two different MacBook Pro models (one integrated Intel graphics and i7, one Radeon graphics and i9), with a Dell U3818DW monitor. Both systems running Catalina 10.15.5 and monitor firmware updated to latest via my Windows machine.

On 10.15.3 and 10.15.4 the power chime, signal search cycle would initiate in sleep mode, both during battery charging and fully charged.

On 10.15.5 the power chime, signal search cycle does not happen during sleep mode while the battery is charging, but start ones the battery is fully charged.

Happy to share video recordings as a proof. This issue has been and total annoyance for me for almost a year now and I'm about to replace the Dell displays with a different brand.