External Display issues , need advice Tahoe

[smogsy]

Setup:
I have two MacBook Pros, one with issues and one working fine.


Devices:

• Personal: MacBook Pro M3 Pro 14" (18GB/512GB)
• Work: MacBook Pro M1 16" (24GB/512GB)

Dock & Displays:

• Both Macs connected via Caldigit TS4
• Display 1: 4K 32" monitor via USB-C → Caldigit
• Display 2: 4K 32" monitor via DisplayPort → Caldigit
• Various USB peripherals (keyboard, mouse, etc.)

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Behavior:


MacBook M1 (work)

• Latest macOS “Tahoe”
• Connected to Caldigit TS4 → works perfectly
• All three screens display correctly (laptop + 2 externals)

MacBook M3 Pro (personal)

• Latest macOS “Tahoe”
• Connects to Caldigit TS4 → only 1 external monitor detected initially
• Quirky behavior:
  • If I hot-plug the monitors in a different order, all three screens work fine.
  • No matter which connector I use for Display 1 (Aorus 4K, OLED), it always gets detected first.
  • If I unplug Display 1 and let the mini-LED 4K then get detected , then replug the other monitor, all 3 displays work perfectly.

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Question:
Has anyone seen this behavior? Any ideas why the M3 Pro behaves differently from the M1 with the exact same dock and monitors?

 

[Basic75]

• Work: MacBook Pro M1 16" (24GB/512GB)

That configuration doesn't exist, which chip is it exactly?

 

[mfram]

The original base M1 only supported one external monitor, I believe. Is that the chip you have?

 

[Bigwaff]

The original base M1 only supported one external monitor, I believe. Is that the chip you have?

There is no “base” M1 16” MBP, only M1 Pro and M1 Max, which both support multiple external displays.

No matter which connector I use for Display 1 (Aorus 4K, OLED), it always gets detected first.

Have you tried both displays via DP or via USB-C?