Hello there

So I want to join multiple MKVs to create a single MKV file. Yes, I know the drill: MKVMerge, Append et al. but you see the thing is the audio tracks on the MKVs are different (some have 5.1, other 2.0 etc.). So what I'd like to know is if I can convert all the MKVs' audio tracks to one format and remux them with a single program? If not, how do I go about this.

Any help would be appreciated, I'm a bit clueless here.

Thanks.