I can confirm that this happens when trying to cast a different spell than the one currently casting.
I don't use a multiplexer feature. In fact my castbar is very simple and a stripped down version from the tutorial.
Code:
["Unitframe_Castbar"] = {
["ty"] = "UnitFrameType",
["version"] = 1,
["data"] = {
{
["feature"] = "var_spellinfo",
}, -- [1]
{
["feature"] = "var_castlag",
}, -- [2]
{
["feature"] = "ColorVariable: Static Color",
["name"] = "lagColor",
["color"] = {
["a"] = 1,
["r"] = 0.5450980392156862,
["g"] = 0.2117647058823529,
["b"] = 0.2078431372549019,
},
}, -- [3]
{
["feature"] = "ColorVariable: Static Color",
["name"] = "castColor",
["color"] = {
["a"] = 1,
["r"] = 1,
["g"] = 0.807843137254902,
["b"] = 0.4705882352941176,
},
}, -- [4]
{
["feature"] = "ColorVariable: Static Color",
["name"] = "channelColor",
["color"] = {
["a"] = 1,
["r"] = 0.3450980392156863,
["g"] = 0.3686274509803922,
["b"] = 1,
},
}, -- [5]
{
["condVar"] = "spell_casting",
["name"] = "castbarColor",
["colorVar1"] = "castColor",
["feature"] = "ColorVariable: Conditional Color",
["colorVar2"] = "channelColor",
}, -- [6]
{
["feature"] = "base_default",
["h"] = 16,
["version"] = 1,
["w"] = 195,
["alpha"] = 1,
}, -- [7]
{
["feature"] = "backdrop",
["owner"] = "Base",
["version"] = 1,
["bkd"] = {
["_border"] = "none",
["bgFile"] = "Interface\\Addons\\VFL\\Skin\\white",
["_backdrop"] = "solid",
["tile"] = false,
["ka"] = 0.621999979019165,
["kb"] = 0.203921568627451,
["kg"] = 0.1176470588235294,
["kr"] = 0.07843137254901961,
},
}, -- [8]
{
["feature"] = "commentline",
}, -- [9]
{
["feature"] = "Description",
["description"] = "yxcycycycyc",
}, -- [10]
{
["feature"] = "Subframe",
["h"] = 16,
["name"] = "lagFrame",
["flOffset"] = 0,
["owner"] = "Base",
["w"] = 195,
["anchor"] = {
["dx"] = 0,
["dy"] = 0,
["lp"] = "TOPLEFT",
["rp"] = "TOPLEFT",
["af"] = "Base",
},
}, -- [11]
{
["frac"] = "spell_fraclag",
["owner"] = "lagFrame",
["w"] = 195,
["feature"] = "statusbar_horiz",
["h"] = 16,
["version"] = 1,
["colorVar"] = "lagColor",
["orientation"] = "HORIZONTAL",
["name"] = "lagBar",
["anchor"] = {
["dx"] = 0,
["dy"] = 0,
["lp"] = "TOPRIGHT",
["rp"] = "TOPRIGHT",
["af"] = "lagFrame",
},
["texture"] = {
["blendMode"] = "BLEND",
["path"] = "Interface\\Addons\\RDX_mediapack\\sharedmedia\\statusbars\\Steel",
},
}, -- [12]
{
["feature"] = "commentline",
}, -- [13]
{
["feature"] = "Subframe",
["h"] = 16,
["name"] = "castFrame",
["flOffset"] = 1,
["owner"] = "Base",
["w"] = 195,
["anchor"] = {
["dx"] = 0,
["dy"] = 0,
["lp"] = "TOPLEFT",
["rp"] = "TOPLEFT",
["af"] = "Base",
},
}, -- [14]
{
["frac"] = "",
["owner"] = "castFrame",
["w"] = 195,
["feature"] = "statusbar_horiz",
["h"] = 16,
["version"] = 1,
["colorVar"] = "castbarColor",
["orientation"] = "HORIZONTAL",
["name"] = "castBar",
["anchor"] = {
["dx"] = 0,
["dy"] = 0,
["lp"] = "TOPLEFT",
["rp"] = "TOPLEFT",
["af"] = "castFrame",
},
["texture"] = {
["blendMode"] = "BLEND",
["path"] = "Interface\\Addons\\RDX_mediapack\\sharedmedia\\statusbars\\Steel",
},
}, -- [15]
{
["script"] = "",
["owner"] = "lagFrame",
["w"] = 195,
["feature"] = "txt_custom",
["font"] = {
["sr"] = 0,
["face"] = "Interface\\Addons\\VFL\\Fonts\\LiberationSans-Regular.ttf",
["justifyV"] = "CENTER",
["sx"] = 1,
["sa"] = 1,
["sg"] = 0,
["name"] = "Default",
["sb"] = 0,
["sy"] = -1,
["title"] = "Default",
["justifyH"] = "RIGHT",
["size"] = 10,
},
["version"] = 1,
["anchor"] = {
["dx"] = -3,
["dy"] = 0,
["lp"] = "RIGHT",
["rp"] = "RIGHT",
["af"] = "lagFrame",
},
["h"] = 16,
["name"] = "timerText",
}, -- [16]
{
["script"] = "",
["owner"] = "castFrame",
["w"] = 195,
["feature"] = "txt_custom",
["font"] = {
["sr"] = 0,
["face"] = "Interface\\Addons\\VFL\\Fonts\\LiberationSans-Regular.ttf",
["justifyV"] = "CENTER",
["sx"] = 1,
["sa"] = 1,
["sg"] = 0,
["name"] = "Default",
["sb"] = 0,
["sy"] = -1,
["title"] = "Default",
["justifyH"] = "LEFT",
["size"] = 10,
},
["version"] = 1,
["anchor"] = {
["dx"] = 3,
["dy"] = 0,
["lp"] = "LEFT",
["rp"] = "LEFT",
["af"] = "castFrame",
},
["h"] = 16,
["name"] = "spellText",
}, -- [17]
{
["feature"] = "commentline",
}, -- [18]
{
["cleanupPolicy"] = 2,
["owner"] = "Base",
["w"] = 16,
["feature"] = "texture",
["h"] = 16,
["version"] = 1,
["anchor"] = {
["dx"] = 0,
["dy"] = 0,
["lp"] = "TOPRIGHT",
["rp"] = "TOPLEFT",
["af"] = "Base",
},
["name"] = "spellIconTex",
["drawLayer"] = "ARTWORK",
["texture"] = {
["color"] = {
["a"] = 1,
["r"] = 1,
["g"] = 1,
["b"] = 1,
},
["blendMode"] = "BLEND",
},
}, -- [19]
{
["TEIDefaultState"] = "Hide",
["textInfo"] = "spellText",
["showduration"] = 1,
["feature"] = "free_timer",
["sbDefaultState"] = "Hide",
["TTIDefaultState"] = "Hide",
["textType"] = "Hundredths",
["statusBar"] = "castBar",
["text"] = "timerText",
["color1"] = {
["a"] = 1,
["b"] = 1,
["g"] = 1,
["r"] = 1,
},
["color2"] = {
["a"] = 1,
["b"] = 1,
["g"] = 1,
["r"] = 1,
},
["countTypeFlag"] = "true",
["version"] = 1,
["tex"] = "spell_icon",
["txt"] = "spell_name_rank",
["timerVar"] = "spell",
["texIcon"] = "spellIconTex",
}, -- [20]
{
["feature"] = "shader_showhide",
["owner"] = "Base",
["version"] = 1,
["flag"] = "spell_castingOrChanneled",
}, -- [21]
},
},