E7000 odd sound

[Benbenben]

Just got my Vitus and loving it, have done about 75k in the last few days, today I stopped on an uphill without changing down gear then tried to restart from zero cadence in boost and the motor made a bit of a weird slipping sound as it tried to engage. It then worked fine for the rest of the ride.
I guess what I did isn’t recommended but is it normal for that to happen?

 

[inwoods]

I have not heard a slipping sound on my E7000 but try not to worry about it, when it breaks it will be replaced so don't let it affect your enjoyment.