all externals : crash when set buffer before audio is turned ON

[Mathieu Chamagne]

Bug Description:
cm.indexcloud~ / cm.buffercloud~ / cm.gausscloud~ : if buffer is changed with a 'set' message BEFORE audio is turned ON, Max crash.
(Mac & Windows)

Reproduction Steps:

----------begin_max5_patcher----------
795.3oc2XtsaiBCD.8YpT+GP7LajuwkzekUqhb.mTWQLQboIsUa+12w1PBaK
oMkzPaCODfwFOLGO2HOc8UNdyy2JJ8buw82tNNOARbLxzRbZE33shuMIiWZl
nm3QdZxyd9MiopWkWWkIpLiRZEakU8vZgc08JkKU7LO+cW49m14tlWkbqTsb
VgHoxN8fPzDjuaDaRfuKKPes928OCnVopUq3VoxTyqX9769EwyH6uWek9Lbx
+nsvUhxR9RwNSrRr07Z4UJpbSxxqSK4qVmInG.B3CBg21nAadJbDGfrGzXvp
oS0H.iXZFPHGjAjdX.dDf.YLf.lbBPfNbHnDafk30LXd8hEhhm+OmA2xayQg
TzDtbwGN5XQVNuRGbLmqV91.BGQ6gPPzglPSwuCg5KTAyFEBQbuKWsL6guF.
gizjYf.J3yGPIqlrjWWVZ.zK3Dk3Bu6GfQriOEKbkTYn1wEywlZOHL.XQlrt
DL88.FsOhEt6sujeuHcFHDT2LdUUgbdcksniydn43UHtWTTJrKwhcdHvBLCL
BQw5t6NfTPjHWKCsS1ihBqDqflsqe70.vHzvS+EcYTB.hoGLBhuvJ.nygA7I
JnIbMRClvgm+e5kU5+dvisOxAl7GcVR9KUohseGS9GiARAccpIEvMc.XHpYL
D8swWu7C+UTJXSmY90VfvciTcdqUzcmiDZaUNBOfDkL1HTrXOOHiAOnAm.OP
muLi68JbmyKL14jM76OmYFY.DX5343F.EDncXNgJGzKrRq8SH5IT8fFMBtPD
2a4JEXJmaOHBiMg0IDKNLpiGzzAvGxk02d1OfZcfFBfnmktOrHpu1O53T8cn
SDJxD0Qw1wZOhiC+3chv9A0Hh0t7xjpW8+yZHmdfWr2WlWWjztIX+tGe2N.J
UTVIU7JYtpyjzsmom0g8xNZ8EMx5CZW4HTH6ySenwUeX5QAzvOOERNAE13wx
WuVGyz7HVcAoktKuPeeru8doxdef8dHNS19H17vd7BH8PEDeVWXi+1F1D+5s
JOUTnpklfOPh1Z0p1j4SwgNQWys1kIC40WAS3e.U2waq
-----------end_max5_patcher-----------

{
"version" : "Beta Version 8.5.2 (940ec4bb5f3) (x64 windows)",
"platform" : "windows",
"arch" : "x64",
"osversion" : "Microsoft Windows 10 (build 19044), 64-bit",
"samplerate" : 44100,
"iovs" : 528,
"sigvs" : 64,
"scheduler_in_audio_interrupt" : "off",
"audio_drivername" : "ad_asio",
"audio_driver_subname" : "FCA1616 USB ASIO x64",
"license" : "permanent full",
"machine_id" : "24d464e7cd48f2abe65be5d74b318d52",
"addons" : {
"rnbo_v1" : "term license"
}
,
"eventinterval" : 2,
"schedinterval" : 1.0,
"overdrive" : "on",
"pollthrottle" : 100,
"queuethrottle" : 1000,
"sysqelemthrottle" : 1000,
"refreshrate" : 30.0,
"schedslop" : 25.0,
"eventprobing" : 1,
"mixerparallel" : "off",
"mixercrossfade" : 0,
"mixerlatency" : 30.0,
"mixerramptime" : 10.0,
"videoengine" : "viddll",
"gfxengine" : "glcore",
"packages" : {
"__MACOSX" : "",
"bach" : "0.8.1",
"BEAP" : "1.0.4",
"boids_max" : "1.0.0",
"bump.map.generator" : "",
"CNMAT Externals" : "1.0.5",
"cv.jit" : "2.0.1",
"dp.kinect2" : "1.2.20200629",
"ease" : "1.2.3",
"FluidCorpusManipulation" : "1.0.4",
"FrameLib" : "1.0.1",
"gl3" : "0.3.3",
"Grainflow" : "1.0.0",
"hap" : "1.0.7",
"ICST Ambisonics" : "3.0.2",
"imp.dmx" : "0.5",
"ISF" : "1.0.3",
"jit.mo" : "1.1.6",
"jit.ndi" : "0.2.0",
"Jitter Tools" : "1.0.5",
"link" : "1.5.5",
"Max Hardware Library" : "1.0.1",
"max-mxj" : "8.2.0",
"Max_Worldmaking_Package-devel" : "",
"maxforlive-elements" : "1.0.6",
"MC_package" : "",
"mi-gen" : "1.1.0",
"Mira" : "1.2.1",
"Miraweb" : "1.2.7",
"MuBu For Max" : "1.10.4",
"MVC-pattr" : "",
"Node for Max" : "2.0.4",
"odot" : "1.3.4",
"OSSIA" : "65c3eeb",
"petra" : "1.2.0",
"RabbitControl" : "1.0.4",
"RISE" : "1.0.4",
"RNBO" : "1.0.2-alpha.2",
"RNBO Guitar Pedals" : "1.0.0",
"RNBO Synth Building Blocks" : "1.1.2",
"Sadam Library" : "20.3.7",
"sensel" : "0.5.1",
"shell" : "",
"SP Tools" : "0.7",
"SPARCK" : "2.0.0",
"spat5" : "5.2.9",
"Spout" : "2.0.73",
"threadcheck" : "",
"VIDDLL" : "1.2.8",
"Vizzie" : "2.2.1",
"VR" : "1.0.1",
"vr.world_recipes" : "",
"XRAY" : "1.0.2",
"XY Coordinates Generator Pack" : "1.0.1",
"zero" : "1.0.4",
"zsa.descriptors" : "1.3.0"
}

}