When you check you System event log after a restart, it contains Event ID 129:
The RSM service is delaying its start for 45 seconds to assist with boot time performance. Modify the registry value "DelayStart" in the registry key "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\NTMS" to modify the start delay. This value denotes the number of milliseconds to wait before starting the service.
If you want the Removable Storage Manager service to start more quickly:
1. Use the Registry Editor to navigate to:
2. Add Value Name DelayStart, a REG_DWORD data type, and set the data value to any number in the range of 1000 through 4294967295 milliseconds, using the Decimal radix.
NOTE: The default value is 45000 milliseconds.