The word miśra has acute accent (udātta) on the final after an Instrumental -3rd case when it is not joined with any Preposition and does not mean a 'compact or alliance'.,
Thus गुडमिश्राः꣡, तिलमिश्राः꣡, सर्पिमिश्राः꣡ ॥ Why do we say मिश्र? Observe गुडधानाः ॥ Why do we say 'not having a Preposition'? Observe गुडसंमिश्राः ॥ The employment in this sutra of the phrase 'anupasargam' implies, that wherever else, the word misra is used, it includes misra with a preposition also. Therefore in 2.1.31 where the word मिश्र is used, we can form the Instrumental compounds with मिश्र preceded by a preposition also. Why do we say 'not denoting a compact'? Observe ब्राह्मणमिश्रो राजा = ब्राह्मणैः सह संहित ऐकार्थ्यमापन्नः ॥ The word सन्धि here means a contract formed by reciprocal promises, if you do this thing for me, I will do this for you. Others say, it means close proximity, without losing identity, and thus differs from मिश्र in which two things blend together into one. Therefore though the King and the Brahmana may be in close proximity as regards space, they both retain their several individualities: hence the counter-example ब्राह्मणमिश्रोराजा ॥ While in the examples गुडमिश्राः &c there is no possibility of separating the two.,