rtl8723bs slow wifi (after kernel 4.18)

wifi slowed down after kernel 4.18

(https://askubuntu.com/questions/756748/inconsistent-connection-and-super-slow-speed-with-rtl8723be) it does not work. thanks
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ProblemType: Bug
ApportVersion: 2.20.9-0ubuntu7.5
Architecture: amd64
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/controlC1', '/dev/snd/pcmC1D1p', '/dev/snd/pcmC1D0c', '/dev/snd/pcmC1D0p', '/dev/snd/by-path', '/dev/snd/controlC0', '/dev/snd/pcmC0D2p', '/dev/snd/pcmC0D1p', '/dev/snd/pcmC0D0p', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
CasperVersion: 1.394
CurrentDesktop: XFCE
DistroRelease: Ubuntu 18.04
LiveMediaBuild: Xubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
Lsusb:
 Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 001 Device 004: ID 058f:5608 Alcor Micro Corp.
 Bus 001 Device 003: ID 058f:6387 Alcor Micro Corp. Flash Drive
 Bus 001 Device 002: ID 6080:8060
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: I-Life Digital Technologies LLC ZED AIR TES
Package: linux (not installed)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=C.UTF-8
 SHELL=/bin/bash
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/username.seed boot=casper quiet splash ---
ProcVersionSignature: Ubuntu 4.18.0-15.16~18.04.1-generic 4.18.20
PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon.
RelatedPackageVersions:
 linux-restricted-modules-4.18.0-15-generic N/A
 linux-backports-modules-4.18.0-15-generic N/A
 linux-firmware 1.173.3
RfKill:
 0: phy0: Wireless LAN
  Soft blocked: no
  Hard blocked: no
StagingDrivers: r8723bs
Tags: bionic staging
Uname: Linux 4.18.0-15-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 12/06/2017
dmi.bios.version: LC-BI-14-Y116CR210-424-B
dmi.board.asset.tag: Default string
dmi.board.name: Cherry Trail CR
dmi.board.vendor: AMI Corporation
dmi.board.version: Default string
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 10
dmi.chassis.version: Default string
dmi.modalias: dmi:bvn:bvrLC-BI-14-Y116CR210-424-B:bd12/06/2017:svnI-LifeDigitalTechnologiesLLC:pnZEDAIRTES:pvrDefaultstring:rvnAMICorporation:rnCherryTrailCR:rvrDefaultstring:cvn:ct10:cvrDefaultstring:
dmi.product.family: Default string
dmi.product.name: ZED AIR TES
dmi.product.sku: Default string
dmi.product.version: Default string
dmi.sys.vendor: I-Life Digital Technologies LLC