Hi, I am Max, i am italian, but based on thailand, i am very expert on a2billing, and starting from your details i can solve your bugs, but thats are very strange bugs.... maybe the version that you had is customized by third party and you will be found problem after when run the business, i suggest to install a new system, i can do it quickly and not too expensive, centos last version 64 bit, asterisk last version, a2billing last version, firewall and security fix all inclusive, i maked also a lot of customization that maybe can interest to you. I am very happy if you would like to have also just a skype meeting for talk, feel free to contact me and indicate time and date, i will be available. If you prefer ask or have some other info not esistate to contact me by message or/and email. Thank you and Best Regards