HDR editing problem in Lightroom

hello, I am currently experiencing problems editing HDR photo in Lightroom. hello, I am currently experiencing problems editing HDR photo in Lightroom. For example, with the adjustment brush, it takes a very long time for the selection to be seen in the photo and often the selection shoots all over the picture. For example, with the adjustment brush, it takes a very long time for the selection to be seen in the photo and often the selection shoots all over the picture. I don't have this problem if I edit a single photo (i.e. not HDR) with it. I don't have this problem if I edit a single photo (i.e. not HDR) with it.

My PC specs. My PC specs. are:

• Windows 10 Home 64bit /
• Intel Core i7 4790K - 4Ghz - Haswell 22nm Techn. Aries: 16Gb Dual-Channel DDR3 - 800MHz (10-10-10-30) /
• Mohterboard: MSI Z97 PC Mate(MS-7850) (socket 0) /
• Graphics: NVIDIA Geforce GTX 760 (MSI) - 2047Mb /
• Storage 232Gb Samsung SSD 840 Evo 250Gb (SATA (SSD)) /
• Ram: 16Gb Dual-Channel DDR3 - 800MHz (10-10-10-30) 

anyone have an idea what the problem may be and how to fix it ??