Because it is a combination of hardware, software and timing.
If you have voltage enabled, the DiseqC command can get "lost" in the voltage puls, so the switch misses it. The original old enigma2 code had a dumb workaround that simply repeated DiseqC commands in the hope they would get to the switch eventually, and that was removed from our codebase quite some time ago because it could have quite an impact on zap speeds.
The downside of this is that you now have to configure your tuner settings properly, while in the past you could get away with not doing it.
You can find it in your tuner configuration, something like "set voltage..." which should be no in case of a multiswitch, as they are only controlled by DiseqC commands.
Currently in use: VU+ Duo 4K (2xFBC S2), VU+ Solo 4K (1xFBC S2), uClan Usytm 4K Ultimate (S2+T2), Octagon SF8008 (S2+T2), Zgemma H9.2H (S2+T2)
Due to my bad health, I will not be very active at times and may be slow to respond. I will not read the forum or PM on a regular basis.
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