Hi @KaitlinDB , thanks for your post. For the pulsing, this can be caused by a either blockage or dirty filter. We found an helpful article that will help pin point the cause. Please visit the link below:

https://community.dyson.com/common-questions-145/my-cordless-vacuum-cleaner-is-pulsing-switching-on-off-has-a-blockage-light-what-does-this-mean-601

@KaitlinDB The Dyson Cyclone V10 models have a system included in them which detects blockages in the vacuum cleaner. If there are any present, the machine starts to make a pulsating noise (as you mentioned). Further, the LED-indicators also start to flash for a minute. 

According to the problem you mentioned, there are possibilities of a blockage in your Dyson V10. You can inspect your vacuum cleaner to find out if that is the problem. Follow the steps below:

1. Disengage your vacuum cleaner’s head from the machine and check for any entanglements present underneath. If present, remove them and check the airways for further blockage.
2. Check the neck of the vacuum cleaner’s head (the point of attachment between the cleaning head and the vacuum cleaner)
3. Next, we’ll move towards the vacuum wand. Disengage it like you did with the cleaner head. Follow the same steps as above, that is, inspecting the component and checking for debris.
4. Lastly, empty your vacuum cleaner’s bin. Then, heavily inspect the surrounding areas  of the Bin, that is, the inlet and other hollow areas. Remove any sort of entanglement or debris that you find.