I have a model that started out working great ... and then some lights quit working.  It is odd that only some of the lights have quit.  I am running Capture 2021.0.34 Student Edition.

Symptoms:

1. Non-functioning lights used to work with no model changes between functionnig and non-functioning.
2. Some lights of the same type work while other lights of the same type do not.
3. The affects of the non-functioning lights can be seen (the model lights up) but the fixtures do not emit a beam nor show any light nor color.
4. I have snooped the ArtNet packets and they show appropriate values being sent to the non-functioning devices.
5. In Capture, checking the DMX values for the fixtures in the univese reveals that the same values are being sent to both functioning and non-functioning lights - yet the lights refuse to light.  This indicates that the problem is with Capture and not the controller nor the network transport.
6. Occasionally the set of non-functioning lights changes - I have yet to discover any correlation with a particular action other than possibly closing Capture and restarting it - although it does not change with each Capture restart.

I have tried the following:

1. Restarting Capture: unchanged - same lights are still non-functioning.
2. Use an older version of the model that was saved prior to the light failures: unchanged - same failures
3. Re-install Capture: this seemed to help temporarily but then the lights (a different set) failed again.
4. Reset Universe Levels: this immediately fixed the model ... but then lights later failed and the Universe -> More -> Reset Levels no longer fixes the problem.
5. Tried Capture 2020.0.55 Student Edition: same failures.

I am waiting to receive a link to the Student Edition of Capture 2021.0.35 with hopes that it has a bug fix for this.