FPP randomly speeds up lights during sequence, fine in XLights

[aplant92]

Has anyone seen this behavior before? When I watch the sequence in XLights, the lights are doing their thing bang on time, yet when I try and run the same sequence from FPP, it seems to randomly speed up then return to normal.

Any ideas what could be causing this?

 

[djgra79]

If you mean speed up, I assume it is stopping or slowing down at some stage?
Are you using unicast for your controllers and if so, are ALL of them plugged in and switched on while you're having this issue?
FPP is known to stutter badly trying to output entire show data on Unicast when not all controllers are connected and powered.
To solve this, you can disable relevant outputs within FPP software.

 

[aplant92]

So for instance, I'm making lights flash to a beat. For the first two beats the lights flash on the beat, then all of a sudden there's a quick flash after the second, then the rest are out of time.

I'm using multicast for the whole setup too!

 

[aplant92]

All looks normal in XLights, and I get no warnings about channel overlaps or anything of the kind in the XLights sequence checker. Really not sure why it's suddenly changing once on the FPP!

 

[aplant92]

Possibly because of the song, but after adding a 250ms offset, it seems to be much better now. Maybe I was getting confused as the first two seemed to be in time. I guess the next question is why is there a 250ms delay in audio coming from the FPP...

 

[Kitman]

I had this exact issue with my first year of running my light show, everything was bang on in Vixen, however when I ran my sequence all of my lights seemed to be doing their own thing and I couldn't figure it out, I thought maybe I was doing something wrong or had set up something wrong or because I was using multiple raspberry Pi's the wireless signal was getting swamped and it couldn't send sync packets.

However after it played through my entire sequence and every song once it was fixed. no more weird timing issues, everything went exactly as it should have for the rest of the season, I put it down to the fact that it might have wanted to perform some kind of timing comparison when it actually played the show but never investigated further, this year I will be "running my show" with no lights connected once before the first light up night and hopefully won't have the issue again.

 

[aplant92]

Thanks for the suggestion, I'll give that a try too! I've got a brand new Pi, micro SD and USB but still getting the same issue, so think I can rule out any of those as the culprits.

Strangely enough 99% of the song seems to be correct, it's just this one bit at the start that seems to speed itself up then return to normal

 

[aplant92]

OK using an OGG file with the same sequence seems to put it in time...yet when I run that same sequence with the OGG in XLights, the lights are behind. Really don't get what's going on here!