[radeon] Videos are getting stuck randomly at frames

Updated Ubuntu to 18.04 (from 17.10) and this problem started. Videos, on VLC and on Youtube, Twitch etc. on Chrome get stuck on frames. The video seek time also gets stuck at that frame, and then suddenly the video skips ahead. Audio has no issues. I am assuming it's a problem with the video drivers.

I have dual graphics cards, one integrated and one dedicated(AMD Radeon HD 8670M). I guess my problem is similar to https://askubuntu.com/questions/1029205/video-playback-performance-issue-ubuntu-18-04

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xorg 1:7.7+19ubuntu7
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Uname: Linux 4.15.0-20-generic x86_64
.tmp.unity_support_test.0:

ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
Date: Tue May 1 19:40:21 2018
DistUpgraded: 2018-04-26 21:50:03,842 ERROR got error from PostInstallScript ./xorg_fix_proprietary.py (g-exec-error-quark: Failed to execute child process “./xorg_fix_proprietary.py” (No such file or directory) (8))
DistroCodename: bionic
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation Haswell-ULT Integrated Graphics Controller [8086:0a16] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Dell Haswell-ULT Integrated Graphics Controller [1028:05ea]
InstallationDate: Installed on 2016-01-21 (830 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
MachineType: Dell Inc. Inspiron 5537
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-20-generic root=UUID=d287f35b-0011-4adf-a2f4-3626718405ff ro quiet splash radeon.modeset=1 vt.handoff=1
SourcePackage: xorg
UpgradeStatus: Upgraded to bionic on 2018-04-26 (4 days ago)
dmi.bios.date: 04/30/2014
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A08
dmi.board.name: 04NGGW
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: A08
dmi.modalias: dmi:bvnDellInc.:bvrA08:bd04/30/2014:svnDellInc.:pnInspiron5537:pvrA08:rvnDellInc.:rn04NGGW:rvrA00:cvnDellInc.:ct8:cvrA08:
dmi.product.family: 00
dmi.product.name: Inspiron 5537
dmi.product.version: A08
dmi.sys.vendor: Dell Inc.
version.compiz: compiz 1:0.9.13.1+18.04.20180302-0ubuntu1
version.libdrm2: libdrm2 2.4.91+git1804271336.50426f~oibaf~b
version.libgl1-mesa-dri: libgl1-mesa-dri 18.2~git1805010730.6487e7~oibaf~b
version.libgl1-mesa-glx: libgl1-mesa-glx 18.2~git1805010730.6487e7~oibaf~b
version.xserver-xorg-core: xserver-xorg-core 2:1.19.6-1ubuntu4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.5-1ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.0.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2