My YouTube is slow! How do I fix it?

The videos I watch will randomly desync the audio and video by seconds or minutes after a brief period of buffering, this has been happening for days. I've tried most basic solutions such as disabling hardware acceleration and repeatedly clearing the cache and such using Ccleaner. I can't seem to find the issue.

{"ns":"yt","el":"detailpage","cpn":"w6MFKRs68mT538BK","docid":"H11U3jOp3MA","ver":2,"referrer":null,"cmt":"42.13","plid":"AAUkOBSjNU2KANsj","ei":"1n1CVsfrF5P1-gXo4Zq4Bw","fmt":"135","fs":"0","rt":"82.694","of":"NSozFX9sqyEp4P-U7Hogvw","adformat":null,"content_v":null,"euri":"","subscribed":"1","lact":9,"live":null,"cl":"107407997","mos":0,"osid":null,"state":"4","vm":"CAEQAQ","volume":68,"c":"WEB","cver":"html5","cplayer":"UNIPLAYER","cbr":"Firefox","cbrver":"42.0","cos":"Windows","cosver":"6.3","hl":"en_US","cr":"US","len":"652.806","fexp":"9408710,9409207,9414764,9415555,9416008,9416126,9416402,9416984,9417097,9417683,9417707,9417828,9418294,9418750,9420453,9421250,9421662,9421905,9422354,9422483,9422541,9422596,9422618,9423510,9423663,9423793,9424198","afmt":"140","allowed":"1_2,1_2_1,1_1,1_3,2_2_1,2_2,2_1,2_3","vct":"42.130","vd":"652.806","vpl":"0.000-27.698,27.898-42.130,","vbu":"26.693-117.400,","vpa":true,"vsk":false,"ven":false,"vpr":1,"vrs":3,"vns":2,"vec":null,"vvol":0.68,"lct":"42.130","lsk":false,"lmf":true,"lbw":"281913.497","lhd":"1.571","ltd":"234.994","laa":"itag=140,seg=11,range=1748839-1867000,time=110.0-117.5","lva":"itag=135,seg=21,range=12699902-13242810,time=112.1-117.5","lar":"itag=140,seg=11,range=1748839-1907530,time=110.0-120.0","lvr":"itag=135,seg=23,range=13981228-14719453,time=122.8-128.1","lvh":"r1---sn-4avf-3pol","lab":"20.016-117.400,","lvb":"26.693-117.451,","ismb":12060000,"debug_videoId":"H11U3jOp3MA","cgr":true,"debug_playbackQuality":"large","debug_date":"Tue Nov 10 2015 18:30:56 GMT-0500 (Eastern Standard Time)"}

/r/youtube Thread