Open config app. Go to path '/modules/dam/config'. And add 'downloadPath' (to change default path '/dam/') property with no value. I just do not have time to add value, module starts to restart. Then you will see this lines in console:

2015-08-18 14:27:23,943 INFO info.magnolia.module.ModuleManagerImpl : Stopping module dam
2015-08-18 14:27:23,961 INFO info.magnolia.module.ModuleManagerImpl : Starting module dam

Press F5 in browser to see this lines

2015-08-18 14:27:30,765 WARN info.magnolia.dam.core.download.DamDownloadServlet: No asset could be found for the following path /
2015-08-18 14:27:30,765 WARN info.magnolia.dam.core.download.DamDownloadServlet: Provider jcr can not support assets search based on path

Voilà. That's all. You never get to console again. You can't change value or remove property. You can't change it in DB.