PowerShell parallel Script Block schluckt erstes Objekt

 $_ | Out-File -FilePath "d:\temp\test\$($_).txt"   

$backupLoc="D:\Sicherungen\Acronis_CB_Local\"  
$expDir="D:\Sicherungen\Acronis_EXP\"  
$successMessage="The operation completed successfully."  
$DateValLen = $("_20240506_080135.ERROR").Length  
$dateFormat = 'dd.MM.yyyy HH:mm:ss'  
# "" Blank ALLE - Mehrach "aaa|bbb|ccc"  
$excludeUID = "WSUS"  
$includeUID = ""  
Function DetermineArcFailed() {
$Script:arc_failed = $(Get-ChildItem -Path $expDir -Filter "*.ERROR" | Where-Object { $_.LastWriteTime.Day -eq (Get-date).Day }).Name `  
| ForEach-Object { $_.ToString().Substring(0,$($_.ToString().Length-$DateValLen)) }
}

$arc_list = acrocmd list archives --loc=$backupLoc --output=raw --all
$arc_list_csv = ConvertFrom-CSV -Delimiter "`t" -InputObject $arc_list -Header "Name","Mode","Date","Appliance","User","Size","VM" | Where-Object { $_.Mode -eq 'disk' } `  
| Select-Object *,@{Name = 'DateTime'; Expression = {[datetime]::ParseExact($_.Date, $dateFormat, [cultureinfo]::InvariantCulture)}} -ExcludeProperty datetime   
$arc_list_csv_orderd = $arc_list_csv | Sort-Object -Property DateTime -Descending | Group-Object -Property 'VM' | ForEach-Object {$_.Group[0]}   

$arc_uid = $arc_list_csv_orderd.Name | Where-Object {$_ -notmatch "$excludeUID" -and $_ -match "$includeUID"}  

$acro_job = $arc_uid  | ForEach-Object -Parallel {        
        $expDirL=$using:expDir
        $backupLocL=$using:backupLoc
        $successMessageL=$using:successMessage
 
        $exportJob = acrocmd export backup --loc=$backupLocL --arc=$_ --target=$expDirL
        if ($($exportJob | Select-Object -Last 1) -eq $successMessageL) {
            $timeStamp=(Get-Date).ToString("yyyyMMdd_HHmmss")  
            $dateStamp=(Get-Date).ToString("yyyy_MM_dd")  
            Rename-Item -Path "$expDirL\$_.tibx" -NewName "$($_)_$timeStamp.tibx"    
            New-Item -Path "$expDirL\$($_)_$timeStamp.OK" -ItemType File         
        } ELSE { 
            New-Item -Path "$expDirL\$($_)_$timeStamp.ERROR" -ItemType File   
        } 
    } -ThrottleLimit 4 -AsJob

$acro_job