This is the etrecheck report:
EtreCheck version: 5.2 (5C006)
Report generated: 2019-05-22 17:32:46
Download EtreCheck from https://etrecheck.com
Runtime: 2:49
Performance: Good

Problem: Beachballing

Major Issues:
    Anything that appears on this list needs immediate attention.

    No Time Machine backup - Time Machine backup not found.

Minor Issues:
    These issues do not need immediate attention but they may indicate future problems or opportunities for improvement.

    Kernel extensions blocked - There are blocked kernel extensions awaiting user approval.

Hardware Information:
    iMac (27-inch, Mid 2011)
    iMac Model: iMac12,2
    1 2,7 GHz Intel Core i5 (i5-2500S) CPU: 4-core
    12 GB RAM - Upgradeable
        BANK 0/DIMM0 - 2 GB DDR3 1333 ok
        BANK 1/DIMM0 - 2 GB DDR3 1333 ok
        BANK 0/DIMM1 - 4 GB DDR3 1333 ok
        BANK 1/DIMM1 - 4 GB DDR3 1333 ok

Video Information:
    AMD Radeon HD 6770M - VRAM: 512 MB
        iMac 2560 x 1440

Drives:
    disk0 - WDC WD1001FALS-403AA0 1.00 TB (Mechanical - 7200 RPM)
    Internal SATA 3 Gigabit Serial ATA
        disk0s1 - EFI (MS-DOS FAT32) [EFI] 210 MB
        disk0s2 - Macintosh HD (Journaled HFS+) 899.00 GB (10.85 GB used)
        disk0s3 - Recovery HD [Recovery] 650 MB
        disk0s4 - B******P (MS-DOS FAT12) 100.34 GB (81.69 GB used)

Mounted Volumes:
    disk0s2 - Macintosh HD 899.00 GB (887.89 GB free)
        Journaled HFS+
        Mount point: /

    disk0s4 - B******P 100.34 GB (18.65 GB free)
        MS-DOS FAT12
        Mount point: /Volumes/B******P

    disk1s2 - R****r 2 MB (20 KB free)
        Mac OS Extended
        Disk Image
        Mount point: /Volumes/R****r
        Owners enabled: No

Network:
    Interface en0: Ethernet
    Interface fw0: FireWire
    Interface en1: Wi-Fi
        802.11 a/b/g/n
    Interface en4: Bluetooth PAN
    Interface bridge0: Thunderbolt Bridge

System Software:
    macOS High Sierra 10.13.6 (17G7024)
    Time since boot: About 8 hours

Security:
    Gatekeeper: Enabled
    System Integrity Protection: Enabled

32-bit Applications:
    None

Kernel Extensions:
    /Library/Extensions
        [Blocked] RMEFirefaceUSB.kext (RME GmbH, 3.15 - SDK 10.11)
        [Blocked] RMEUSBNetworkDriver.kext (RME GmbH, 1.0.1 - SDK 10.11)

System Launch Agents:
    [Not Loaded] 15 Apple tasks
    [Loaded] 168 Apple tasks
    [Running] 111 Apple tasks

System Launch Daemons:
    [Not Loaded] 37 Apple tasks
    [Loaded] 188 Apple tasks
    [Running] 110 Apple tasks

Launch Agents:
    [Running] de.rme-audio.RMEfirefaceUSBAgent.plist (RME GmbH - installed 2019-02-14)

Launch Daemons:
    [Loaded] com.apple.installer.osmessagetracing.plist (Apple - installed 2019-05-08)

Audio Plug-ins:
    BluetoothAudioPlugIn: 6.0.7 (Apple - installed 2019-05-21)
    iSightAudio: 7.7.3 (Apple - installed 2019-05-21)
    AirPlay: 2.0 (Apple - installed 2019-05-21)
    AppleAVBAudio: 683.1 (Apple - installed 2019-05-21)
    BridgeAudioSP: 4.69.2 (Apple - installed 2019-05-21)
    AppleTimeSyncAudioClock: 1.0 (Apple - installed 2019-05-21)

Time Machine:
    Time Machine Not Configured!

Performance:
    System Load: 1.23 (1 min ago) 1.06 (5 min ago) 1.03 (15 min ago)
    Nominal I/O speed: 0.11 MB/s
    File system: 19.43 seconds
    Write speed: 132 MB/s
    Read speed: 132 MB/s

Top Processes Snapshot by CPU:
    Process (count) CPU (Source - Location)
    WindowServer 4.24 % (Apple)
    EtreCheckPro 4.20 % (Etresoft, Inc.)
    Activity Monitor 2.84 % (Apple)
    kernel_task 1.15 % (Apple)
    sysmond 0.74 % (Apple)

Top Processes Snapshot by Memory:
    Process (count) RAM usage (Source - Location)
    kernel_task 753 MB (Apple)
    com.apple.WebKit.WebContent (5) 523 MB (Apple)
    EtreCheckPro 438 MB (Etresoft, Inc.)
    WindowServer 111 MB (Apple)
    mdworker (6) 108 MB (Apple)

Top Processes Snapshot by Network Use:
    Process Input / Output (Source - Location)
    com.apple.WebKit.Networking 10 MB / 2 KB (Apple)
    mDNSResponder 523 KB / 261 KB (Apple)
    apsd 24 KB / 21 KB (Apple)
    netbiosd 26 KB / 5 KB (Apple)
    SystemUIServer 0 B / 464 B (Apple)

Top Processes Snapshot by Energy Use:
    Process (count) Energy (0-100) (Source - Location)
    WindowServer 3 (Apple)
    Activity Monitor 1 (Apple)
    sysmond 0 (Apple)
    dasd 0 (Apple)
    UserEventAgent (2) 0 (Apple)

Virtual Memory Information:
    Physical RAM: 12 GB

    Free RAM: 8.04 GB
    Used RAM: 3.06 GB
    Cached files: 919 MB

    Available RAM: 8.94 GB
    Swap Used: 0 B

Software Installs (past 30 days):
    Install Date Name (Version)
    2019-05-21 MRTConfigData (1.41)
    2019-05-21 XProtectPlistConfigData (2103)
    2019-05-21 Gatekeeper Configuration Data (166)
    2019-05-21 Safari (12.1.1)
    2019-05-21 iTunes (12.8.2)
    2019-05-21 Security Update 2019-003 (10.13.6)
    2019-05-22 Fireface USB Driver (315)

Diagnostics Information (past 7 days):
    2019-05-22 00:30:18 Finder.app Hang
        Executable: /System/Library/CoreServices/Finder.app

    2019-05-21 23:56:05 Software Update.app Memory
        Executable: /System/Library/CoreServices/Software Update.app


End of report