Assalamu Alaikum ustadh. If someone gets some thoughts in salah and they try to not laugh, but their sound/voice changes due to them suppressing their laughter, can this be considered as nullifying salah ? JazakaAllahu Khairan

Ustadh AbdulAziz al-Haqqan

No, but don't enter the salah with your mind busy like that, but with humility and humbleness in front of Allah. This should be your mentality before you enter into any salah.