1: There is a creditor-debtor relationship between Party A and Party A, Party B and Party C, with Party A as the debtor and Party A, Party B and Party C as the creditors. After that, Party A paid the hotel audio equipment 60,000 yuan to compensate the above three people, so the creditor-debtor relationship between the two parties was terminated due to repayment; The relationship between Party A and Party D is a sales contract; 2. The agreement between the hotel and the original defendant to pay off the debt by audio is valid-the agreement between the two parties meets the effective conditions. 3. If Party A sells the stereo without the consent of Party B and Party C, can Buyer D acquire the ownership-not necessarily; Except that Party D doesn't know that the audio equipment is owned by Party A, Party B and Party C, Party D can't obtain the ownership under other circumstances (unless Party B and Party C agree); 4. Answer: On the premise that the sales contract between Party A and Party D is valid, Party A shall compensate Party C with RMB 654.38+0,000 and its interest; The reason is that the audio equipment belongs to Party A, Party B and Party C, and Party A has no right to dispose of it alone. Therefore, if Party A is at fault, it shall be liable for the losses of Party C, while Party B only gets its share, and there is no fault in this incident, so it shall not be liable; B: On the premise that the sales contract between Party A and Party D is invalid, both parties shall return the property within X days (that is, restore it to the state before the contract is concluded). Reject other claims;