In Vegas 23 I added a fade out to a clip and when the fade begins the playback and rendered clip has corrupted video during the fade. Here are links to the source media and rendered clip showing the problem.
https://1drv.ms/u/c/9260499e24dffbe8/EbIUSWB6D5tDsUveXZRFaCQBG1MnfRSHPe_Uc0P2F_CNGQ?e=XqQaL0
https://1drv.ms/v/c/9260499e24dffbe8/EUyrRRCMqX9CvmwATzAxXcoBJXdJ-Pp6t_3zLCr1qpDAcg?e=iudnDv
General
ID : 1 (0x1)
Complete name : C:\Users\Andrew\Videos\2012 Magaluf\Batch1\00008.m2ts
CompleteName_Last : C:\Users\Andrew\Videos\2012 Magaluf\Batch1\00133.m2ts
Format : BDAV
Format/Info : Blu-ray Video
File size : 5.93 GiB
Duration : 13 s 380 ms
Overall bit rate mode : Variable
Overall bit rate : 3 804 Mb/s
Maximum Overall bit rate : 18.0 Mb/s
Frame rate : 25.000 FPS
Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Format settings, GOP : M=3, N=12
Codec ID : 27
Duration : 13 s 362 ms
Bit rate mode : Variable
Bit rate : 3 653 Mb/s
Maximum bit rate : 16.8 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 25.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan type, store method : Separated fields
Scan order : Top Field First
Bits/(Pixel*Frame) : 70.470
Stream size : 5.68 GiB (96%)
Audio
ID : 4352 (0x1100)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Commercial name : Dolby Digital
Codec ID : 129
Duration : 13 s 474 ms
Bit rate mode : Constant
Bit rate : 384 kb/s
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Delay relative to video : -80 ms
Stream size : 632 KiB (0%)
Service kind : Complete Main
Dialog Normalization : -31 dB
compr : -6.58 dB
cmixlev : -3.0 dB
surmixlev : -3 dB
dialnorm_Average : -31 dB
dialnorm_Minimum : -31 dB
dialnorm_Maximum : -31 dB