We visit San Diego regularly, specifically Little Italy. We have never been in a situation where the host provided ear plugs on every night stand in the house. What was supposed to be a pleasant trip to see family and friends for Thanksgiving became a weekend nightmare. The train would be going by close to every 10-15 minutes all night long. We would hear this ringing all throughout the night and to the point where when the ringing would stop, it would continue to play in our head. We got absolutely no prior knowledge of this issue, resulting in no sleep for 2 nights. Consequently, we cut our trip short before the third night to get some much needed sleep. Safe to say we will never stay here again, and would strongly suggest that anyone who would have an issue with this stay far far away from this place. We travel to San Diego at least twice a month, and can without a doubt say this was the worst experience we have ever had there.
You can search on youtube, "nightmare vacation in little italy" to see and hear what I am talking about.