The present invention relates to TRPV1 modulator compounds of formula (I) or their pharmaceutically or veterinary acceptable salts, or their stereoisomers or mixtures thereof, wherein m is an integer selected from 1 to 3; R1, R2, R6 and R6', are independently selected from H, (C1-C8)alkyl, unsaturated (C2-C8)hydrocarbon, and (C3-C6)cycloalkyl, being these groups optionally substituted; R3 is hydrogen or halogen; R4 is selected from H, (C1-C8)alkyl, unsaturated (C2-C8)hydrocarbon, (C3-C6)cycloalkyl, (C6-C12)aryl, and (C5-C12)heteroaryl, being these groups optionally substituted; and R5 is selected from (C3-C28)alkyl, unsaturated (C3-C28)hydrocarbon, (C6-C12)aryl, and (C5-C12)heteroaryl, being these groups optionally substituted. It also relates to a process for their preparation, to pharmaceutical, veterinary or cosmetic compositions containing them, and to their pharmaceutical, veterinary and cosmetic applications.