I have an issue with the ABS-system on my X-Type.

When I brake, sometimes it will feel like the brake-pedal suddenly pushback. Some say it is caused by a leak in the vacuum in the brake booster, but this is not the case, it doesn't feel that way, and I have now tested to revome the ABS fuse, and then the problem seems to be gone. Drove quite a bit without fuse and the problem didn't occur a single time.

Any ideas what could be causing a problem like this?