Problem with hd channels

hello guys , i have this problem with hd channels only .....every time i go to watch hd channels after a little time the picture become very baaad and when i change the channel and return to it again the picture back to normal but after a little time the problem repeats again,,,.....first i thought this is a software problem i was on android 7 which was the thr factory sw then i install android 6 moded by malaysk whish is supereb but also found the same problem...now i think it is a hardware problem .....So,.any one know solution for this frustrating problem???||||||

Quote from kimov

Do a factory reset first, if the HD still not work, try to change the hdmi cable

thanks for repling i will try and inform u