Speaking during তাওয়াফ is permissible and does not invalidate it. নবী করীম (সাল্লাল্লাহু আলাইহি ওয়া সাল্লাম) said: 'তাওয়াফ around the House is like সালাত, except that Allah has permitted speaking in it. So whoever speaks in it, let him speak only good.' This hadith establishes that while talking is allowed, it should be purposeful and good speech rather than idle chatter.
The মুস্তাহাব practice during তাওয়াফ is to engage in dhikr (remembrance of Allah), dua (দোয়া), istighfar (seeking forgiveness), and কুরআন recitation. You may supplicate in any language — Arabic is not required for personal duas. There are no specific mandatory duas assigned to each circuit, despite what some printed তাওয়াফ dua booklets may suggest. Those circuit-specific duas are later compilations, not from নবী করীম's practice. The only Sunnah-specific dua is between the Yamani corner and the হাজরে আসওয়াদ: 'Rabbana atina fi'd-dunya hasanah wa fi'l-akhirati hasanah wa qina adhab an-nar.'
Brief necessary conversation with companions — such as coordinating meeting points, checking on someone's well-being, or answering important questions — is fine. However, extended worldly discussions, arguments, gossiping, phone calls about business, and loud talking that disturbs others should be avoided. Use the precious time of তাওয়াফ to connect with Allah through heartfelt দোয়া.