[Q] Jellytime battery drain when using apps topic

Hi, I just had the jelly time r11 4.2 for a few days, I really like the rom.
The only problem is battery drain. It is ok when standby. But when I try to use apps e.g. Web browser, the battery drain is amazing, almost 2% per minute. I tried to read through some posts, but I can not find solution.
I an wondering if anyone could help.
Thanks a lot.