Mac taking too long to mount external hard drives

AdrianPS wrote:

Hi, I have an external SSD m2 connected using one USB-C by using a Satechi adapter that I use as expanded storage in my mac and then I have an external HDD from Western Digital using one USB port.

When I turn on my Mac, it takes several minutes to mount those external drives and sometimes the OS refuses to mount them directly and I have to go to the Disk Utility app to mount them. No changes have been made to the software using those disks or the login items. Everything worked fine at the beginning and got progressively worse over time.

Thank you for your help.

If no resolve try SafeBoot How to use safe mode on your Mac - Apple Support to sort anomalies.

if no insight or resolve you can file a bug report /submit your Apple Feedback here: Product Feedback - Apple