If the current is 12V, it is 95Ah, which means that it takes about 100Ah for the battery to support one hour of use. Specific use will not usually run at full power, so the actual power consumption is not calculable, it has to do with your volume level, and the sound signal varies randomly.
The 12V battery is only 6V, the possible reasons are caused by over-discharge, or it may be a single cell short circuit. If it is a single cell short circuit problem can not be maintained, can only be scrapped to replace the battery. If it is caused by over-discharge, you can try to repair.