Running out of Space

We have a centralized managed vault that is quickly running out of space. Every day, free space decreases by 300MB-800MB which we believe should not be happening. There are currently 143 archives and 1109 backups. This is a deduplicating vault. On September 18, 2014, free space was 1.2 TB, and today Oct. 16, 2014, it is down to 849 GB free out of a total capacity of 2.5 TB. The vault is stored on a SAN and it is being managed by a dedicated storage node. Only this vault is being managed by the storage node. We're using custom backup scheme, 4 incrementals (Mon-Thur) and 1 full (Fri). Retention rules are set to delete backups older than 7 days. Compaction is scheduled weekly on Sunday at 3AM. There are event log entries for when compacting task starts but I don't see any indication in the logs that compacting task has completed and I don't see any way to monitor its progress. Please see attachment for vault statistics.

One of the reasons for purchasing this product is to save on storage and it's projected to use a lot more space than the previous product that we used even after following Deduplication best practices. We are very unhappy with our situation and with the product unless this can be rectified. Contacting Acronis support via telephone has not gotten us anywhere since initial call a month ago. In comparison, we have a second centralized managed vault on a different storage node which happens to be on the AMS; it has 79 archives and 643 backups. Free space on this one decreased gradually for a couple of weeks then increased for a week then started decreasing again. Any help would be greatly appreciated. Below are the specs of the storage node server:

Operating System: Windows Server 2008 R2 Enterprise with SP1 (x64)
Server Hardware: ProLiant DL360p Gen8
Processor: Intel Xeon CPU E5-2650 0 @ 2.00GHz (2 processors)
RAM: 128 GB