Powershell Export-to-CSV of array providing array properties

This code:

$concerningMachines = @()
foreach($aMachine in $machineRecords.GetEnumerator())
{
    if($aMachine.Value.ReviewScore -gt $averageAboveAverage)
    {
        $machine = New-Object -TypeName PSObject
        $machine | Add-Member -MemberType NoteProperty -Name MachineName -Value $aMachine.Key
        $machine | Add-Member -MemberType NoteProperty -Name ManagedBy -Value $aMachine.Value.ManagedBy
        $machine | Add-Member -MemberType NoteProperty -Name LastLogin -Value $aMachine.Value.LastLogin
        $machine | Add-Member -MemberType NoteProperty -Name ReviewScore -Value ($aMachine.Value.ReviewScore / $averageAboveAverage * 100)
        $concerningMachines += $machine
    }
}

Export-Csv -InputObject $concerningMachines -Path C:\DG\ConcerningMachines.csv -NoTypeInformation

Produces this .csv file:

"Count","Length","LongLength","Rank","SyncRoot","IsReadOnly","IsFixedSize","IsSynchronized" "43","43","43","1","System.Object[]","False","True","False"

...Which is the properties of the array, and not the members of the array. Googling the only advice I find seems to either implement a solution that entire ignores Export-Csv, is dealing with strings (which while collections of characters, the solutions aren't applicable) or appear to be doing exactly what I'm already doing but produce a valid CSV file (I can find some links if needed, but they're forum conversations, not explicit guides).

How do you properly export an array of PSObjects into a CSV files, and avoid the above unintended output?