cylinder 4 misfires
 

2001 stage 3 S4 that has miss fires under load. Did coil pac conversion about 4 years ago. Now I am geeting misses Sometimes at low load sometimes only at high boost. No rhyme or reason. This is what I ve done:
1. swapped coil pac/plug
2. swapped injectors
3. Compression test (no diff between cylinders 4 and 3)
4. changed connector on coil connector

I have a VAGCOM, anything else I should try. Leakdown test may be in order?