beeline spool Hive puts special character instead of quote

I am exporting query results form hive using beeline, here is my command :

beeline -u 'jdbc:hive2://myhost.com:10000/mydb;principal=hive/myhost.COM'  --incremental=true --silent=true  --outputformat=dsv --disableQuotingForSV=true --delimiterForDSV=\, --showHeader=false --nullemptystring=true  -f myquery.hql --hiveconf DT_ID=${DT_ID} > ${spoolFile} 

This is my query :

SELECT id, concat('"',c_name,'"'), app_name from mytab where dt_id='${hiveconf:DT_ID}';

But I get results like this, for fields having my field separator(,) in column value:

66,**^@**"(Chat\, Social\, Music\, Utilities)"**^@**,Default

Note the ^@. Why is it coming? How can avoid it? What is that character? If it is quote, I am to have it, so that I can remove the concat in my query. I tried playing with --disableQuotingForSV=true/false. But that did not help me.