diff --git a/sys/dev/usb/quirk/usb_quirk.c b/sys/dev/usb/quirk/usb_quirk.c
index fdae36843ea5..2872e6d41ddc 100644
--- a/sys/dev/usb/quirk/usb_quirk.c
+++ b/sys/dev/usb/quirk/usb_quirk.c
@@ -333,7 +333,7 @@ static struct usb_quirk_entry usb_quirks[USB_DEV_QUIRKS_MAX] = {
 	    UQ_MSC_FORCE_PROTO_SCSI, UQ_MSC_IGNORE_RESIDUE,
 	    UQ_MSC_NO_START_STOP),
 	USB_QUIRK(PROLIFIC, PL2506, 0x0000, 0xffff,
-	    UQ_MSC_NO_SYNC_CACHE),
+	    UQ_MSC_NO_SYNC_CACHE, UQ_MSC_NO_PREVENT_ALLOW),
 	USB_QUIRK_VP(USB_VENDOR_SAMSUNG_TECHWIN,
 	    USB_PRODUCT_SAMSUNG_TECHWIN_DIGIMAX_410, UQ_MSC_FORCE_WIRE_BBB,
 	    UQ_MSC_FORCE_PROTO_SCSI, UQ_MSC_NO_INQUIRY),